<PAGE>
FILE NO. 333-28537
RULE 424(B)(3)
PROSPECTUS SUPPLEMENT
(TO PROSPECTUS DATED JULY 7, 1997)
(TO PROSPECTUS SUPPLEMENT DATED JULY 7, 1997)
PROSPECTUS NUMBER: 1624
DATED: DECEMBER 9, 1997
MERRILL LYNCH & CO., INC.
MEDIUM-TERM NOTES, SERIES B
DUE NINE MONTHS OR MORE FROM DATE OF ISSUE
FLOATING RATE NOTES
<TABLE>
<CAPTION>
<S> <C>
BASE RATE: Fed Funds (Prior Day H.15)
INDEX MATURITY: One Day
TRADE DATE: December 9, 1997
SETTLEMENT DATE: December 12, 1997
MATURITY DATE: December 14, 1998
REDEMPTION DATE: N/A
OPTIONAL REPAYMENT DATES: N/A
SPREAD: 0.150%
SPREAD MULTIPLIER: N/A
COMMISSION: 0.075%
MAXIMUM INTEREST RATE: N/A
MINIMUM INTEREST RATE: N/A
INTEREST RESET DATES: Daily
INTEREST PAYMENT DATES: The 14th of March, June, September and December commencing March 1998
through Maturity, subject to Following Business Day Convention.
INITIAL INTEREST RATE: TBD, December 12, 1997
FORM: Book-entry
</TABLE>