121515912 has 96 divisors (see below), whose sum is σ = 377657280. Its totient is φ = 34577280.

The previous prime is 121515857. The next prime is 121515913. The reversal of 121515912 is 219515121.

121515912 is a `hidden beast` number, since 1 + 21 + 51 + 591 + 2 = 666.

It is a super-2 number, since 2×121515912² = 29532233738383488, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121515913) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 232083 + ... + 232605.

It is an arithmetic number, because the mean of its divisors is an integer number (3933930).

Almost surely, 2^121515912 is an apocalyptic number.

121515912 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121515912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188828640).

121515912 is an abundant number, since it is smaller than the sum of its proper divisors (256141368).

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

121515912 is a wasteful number, since it uses less digits than its factorization.

121515912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1003 (or 996 counting only the distinct ones).

The product of its digits is 900, while the sum is 27.

The square root of 121515912 is about 11023.4256018717. The cubic root of 121515912 is about 495.3107078992.

The spelling of 121515912 in words is "one hundred twenty-one million, five hundred fifteen thousand, nine hundred twelve".