121015535520 has 96 divisors (see below), whose sum is σ = 415853403840. Its totient is φ = 29337098240.

The previous prime is 121015535449. The next prime is 121015535551. The reversal of 121015535520 is 25535510121.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11454525 + ... + 11465084.

It is an arithmetic number, because the mean of its divisors is an integer number (4331806290).

Almost surely, 2^121015535520 is an apocalyptic number.

121015535520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121015535520 is an abundant number, since it is smaller than the sum of its proper divisors (294837868320).

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

121015535520 is a wasteful number, since it uses less digits than its factorization.

121015535520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22919638 (or 22919630 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 30.

The spelling of 121015535520 in words is "one hundred twenty-one billion, fifteen million, five hundred thirty-five thousand, five hundred twenty".