21231220133313 has 8 divisors (see below), whose sum is σ = 31453659456800. Its totient is φ = 14154146755524.

The previous prime is 21231220133311. The next prime is 21231220133317. The reversal of 21231220133313 is 31333102213212.

21231220133313 is a `hidden beast` number, since 2 + 1 + 2 + 312 + 2 + 0 + 1 + 33 + 313 = 666.

It is not a de Polignac number, because 21231220133313 - 2¹ = 21231220133311 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 786341486419 = 21231220133313 / (2 + 1 + 2 + 3 + 1 + 2 + 2 + 0 + 1 + 3 + 3 + 3 + 1 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21231220133311) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 393170743183 + ... + 393170743236.

It is an arithmetic number, because the mean of its divisors is an integer number (3931707432100).

Almost surely, 2^{21231220133313} is an apocalyptic number.

It is an amenable number.

21231220133313 is a deficient number, since it is larger than the sum of its proper divisors (10222439323487).

21231220133313 is an equidigital number, since it uses as much as digits as its factorization.

21231220133313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786341486428 (or 786341486422 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 27.

Adding to 21231220133313 its reverse (31333102213212), we get a palindrome (52564322346525).

The spelling of 21231220133313 in words is "twenty-one trillion, two hundred thirty-one billion, two hundred twenty million, one hundred thirty-three thousand, three hundred thirteen".