12921575238 has 72 divisors (see below), whose sum is σ = 33140531424. Its totient is φ = 3614418720.

The previous prime is 12921575201. The next prime is 12921575257. The reversal of 12921575238 is 83257512921.

12921575238 is a `hidden beast` number, since 1 + 29 + 21 + 575 + 2 + 38 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 12921575193 and 12921575202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 199870 + ... + 256497.

Almost surely, 2^12921575238 is an apocalyptic number.

12921575238 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12921575238 is an abundant number, since it is smaller than the sum of its proper divisors (20218956186).

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

12921575238 is a wasteful number, since it uses less digits than its factorization.

12921575238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456410 (or 456396 counting only the distinct ones).

The product of its digits is 302400, while the sum is 45.

The spelling of 12921575238 in words is "twelve billion, nine hundred twenty-one million, five hundred seventy-five thousand, two hundred thirty-eight".