21331262056 has 32 divisors (see below), whose sum is σ = 43079702400. Its totient is φ = 9843606720.

The previous prime is 21331262041. The next prime is 21331262129. The reversal of 21331262056 is 65026213312.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 843565 + ... + 868483.

It is an arithmetic number, because the mean of its divisors is an integer number (1346240700).

Almost surely, 2^21331262056 is an apocalyptic number.

21331262056 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21331262056 is an abundant number, since it is smaller than the sum of its proper divisors (21748440344).

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

21331262056 is a wasteful number, since it uses less digits than its factorization.

21331262056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33169 (or 33165 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 31.

Adding to 21331262056 its reverse (65026213312), we get a palindrome (86357475368).

The spelling of 21331262056 in words is "twenty-one billion, three hundred thirty-one million, two hundred sixty-two thousand, fifty-six".