12921538 has 16 divisors (see below), whose sum is σ = 23114880. Its totient is φ = 5296896.

The previous prime is 12921527. The next prime is 12921583. The reversal of 12921538 is 83512921.

It is a super-2 number, since 2×12921538² = 333932288570888, which contains 22 as substring.

It is a zygodrome in base 3.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19743 + ... + 20386.

It is an arithmetic number, because the mean of its divisors is an integer number (1444680).

Almost surely, 2^12921538 is an apocalyptic number.

12921538 is a deficient number, since it is larger than the sum of its proper divisors (10193342).

12921538 is a wasteful number, since it uses less digits than its factorization.

12921538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40161.

The product of its digits is 4320, while the sum is 31.

The square root of 12921538 is about 3594.6540862787. The cubic root of 12921538 is about 234.6594614947.

The spelling of 12921538 in words is "twelve million, nine hundred twenty-one thousand, five hundred thirty-eight".