21331320351255 has 48 divisors (see below), whose sum is σ = 38537561327616. Its totient is φ = 10902823231680.

The previous prime is 21331320351239. The next prime is 21331320351277. The reversal of 21331320351255 is 55215302313312.

21331320351255 is a `hidden beast` number, since 2 + 1 + 3 + 3 + 132 + 0 + 3 + 512 + 5 + 5 = 666.

It is not a de Polignac number, because 21331320351255 - 2⁴ = 21331320351239 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 74085777 + ... + 74373146.

It is an arithmetic number, because the mean of its divisors is an integer number (802865860992).

Almost surely, 2^{21331320351255} is an apocalyptic number.

21331320351255 is a deficient number, since it is larger than the sum of its proper divisors (17206240976361).

21331320351255 is a wasteful number, since it uses less digits than its factorization.

21331320351255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148459068 (or 148459065 counting only the distinct ones).

The product of its (nonzero) digits is 81000, while the sum is 36.

Adding to 21331320351255 its reverse (55215302313312), we get a palindrome (76546622664567).

The spelling of 21331320351255 in words is "twenty-one trillion, three hundred thirty-one billion, three hundred twenty million, three hundred fifty-one thousand, two hundred fifty-five".