21213511590988 has 24 divisors (see below), whose sum is σ = 39081947627520. Its totient is φ = 10047367305360.

The previous prime is 21213511590913. The next prime is 21213511590989. The reversal of 21213511590988 is 88909511531212.

It is a super-2 number, since 2×21213511590988² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21213511590989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15132556 + ... + 16474867.

It is an arithmetic number, because the mean of its divisors is an integer number (1628414484480).

Almost surely, 2^{21213511590988} is an apocalyptic number.

It is an amenable number.

21213511590988 is a deficient number, since it is larger than the sum of its proper divisors (17868436036532).

21213511590988 is a wasteful number, since it uses less digits than its factorization.

21213511590988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31616277 (or 31616275 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 55.

The spelling of 21213511590988 in words is "twenty-one trillion, two hundred thirteen billion, five hundred eleven million, five hundred ninety thousand, nine hundred eighty-eight".