21214036536656 has 40 divisors (see below), whose sum is σ = 42625546957800. Its totient is φ = 10215719628800.

The previous prime is 21214036536617. The next prime is 21214036536677. The reversal of 21214036536656 is 65663563041212.

It can be written as a sum of positive squares in 4 ways, for example, as 15829130645056 + 5384905891600 = 3978584^2 + 2320540^2 .

It is a congruent number.

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, 56821301 + ... + 57193428.

It is an arithmetic number, because the mean of its divisors is an integer number (1065638673945).

Almost surely, 2^{21214036536656} is an apocalyptic number.

It is an amenable number.

21214036536656 is an abundant number, since it is smaller than the sum of its proper divisors (21411510421144).

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

21214036536656 is a wasteful number, since it uses less digits than its factorization.

21214036536656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114015167 (or 114015161 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 50.

Adding to 21214036536656 its reverse (65663563041212), we get a palindrome (86877599577868).

The spelling of 21214036536656 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, five hundred thirty-six thousand, six hundred fifty-six".