21731796755990 has 32 divisors (see below), whose sum is σ = 40481132037984. Its totient is φ = 8393217131520.

The previous prime is 21731796755969. The next prime is 21731796756083. The reversal of 21731796755990 is 9955769713712.

It is a congruent number.

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, 224129339 + ... + 224226278.

It is an arithmetic number, because the mean of its divisors is an integer number (1265035376187).

Almost surely, 2^{21731796755990} is an apocalyptic number.

21731796755990 is a deficient number, since it is larger than the sum of its proper divisors (18749335281994).

21731796755990 is a wasteful number, since it uses less digits than its factorization.

21731796755990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448355792.

The product of its (nonzero) digits is 225042300, while the sum is 71.

The spelling of 21731796755990 in words is "twenty-one trillion, seven hundred thirty-one billion, seven hundred ninety-six million, seven hundred fifty-five thousand, nine hundred ninety".