121987551424 has 28 divisors (see below), whose sum is σ = 249877730368. Its totient is φ = 59026233600.

The previous prime is 121987551421. The next prime is 121987551437. The reversal of 121987551424 is 424155789121.

It is not an unprimeable number, because it can be changed into a prime (121987551421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30740847 + ... + 30744814.

It is an arithmetic number, because the mean of its divisors is an integer number (8924204656).

Almost surely, 2^121987551424 is an apocalyptic number.

It is an amenable number.

121987551424 is an abundant number, since it is smaller than the sum of its proper divisors (127890178944).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121987551424 is an equidigital number, since it uses as much as digits as its factorization.

121987551424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61485704 (or 61485694 counting only the distinct ones).

The product of its digits is 806400, while the sum is 49.

The spelling of 121987551424 in words is "one hundred twenty-one billion, nine hundred eighty-seven million, five hundred fifty-one thousand, four hundred twenty-four".