21021002131 has 2 divisors, whose sum is σ = 21021002132. Its totient is φ = 21021002130.

The previous prime is 21021002111. The next prime is 21021002137. The reversal of 21021002131 is 13120012012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21021002131 - 2⁷ = 21021002003 is a prime.

It is a super-2 number, since 2×21021002131² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21021002137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510501065 + 10510501066.

It is an arithmetic number, because the mean of its divisors is an integer number (10510501066).

Almost surely, 2^21021002131 is an apocalyptic number.

21021002131 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021002131 is an equidigital number, since it uses as much as digits as its factorization.

21021002131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21021002131 its reverse (13120012012), we get a palindrome (34141014143).

The spelling of 21021002131 in words is "twenty-one billion, twenty-one million, two thousand, one hundred thirty-one".