21246835938656 has 24 divisors (see below), whose sum is σ = 41849355973320. Its totient is φ = 10618428072448.

The previous prime is 21246835938649. The next prime is 21246835938697. The reversal of 21246835938656 is 65683953864212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155865086 + ... + 156001341.

It is an arithmetic number, because the mean of its divisors is an integer number (1743723165555).

Almost surely, 2^{21246835938656} is an apocalyptic number.

It is an amenable number.

21246835938656 is a deficient number, since it is larger than the sum of its proper divisors (20602520034664).

21246835938656 is a wasteful number, since it uses less digits than its factorization.

21246835938656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311868566 (or 311868558 counting only the distinct ones).

The product of its digits is 447897600, while the sum is 68.

The spelling of 21246835938656 in words is "twenty-one trillion, two hundred forty-six billion, eight hundred thirty-five million, nine hundred thirty-eight thousand, six hundred fifty-six".