21213301993831 has 2 divisors, whose sum is σ = 21213301993832. Its totient is φ = 21213301993830.

The previous prime is 21213301993811. The next prime is 21213301993883. The reversal of 21213301993831 is 13839910331212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21213301993831 is a prime.

It is a super-2 number, since 2×21213301993831² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21213301993811) 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 as a sum of consecutive naturals, namely, 10606650996915 + 10606650996916.

It is an arithmetic number, because the mean of its divisors is an integer number (10606650996916).

Almost surely, 2^{21213301993831} is an apocalyptic number.

21213301993831 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213301993831 is an equidigital number, since it uses as much as digits as its factorization.

21213301993831 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 209952, while the sum is 46.

The spelling of 21213301993831 in words is "twenty-one trillion, two hundred thirteen billion, three hundred one million, nine hundred ninety-three thousand, eight hundred thirty-one".