21102025939 has 2 divisors, whose sum is σ = 21102025940. Its totient is φ = 21102025938.

The previous prime is 21102025933. The next prime is 21102025957. The reversal of 21102025939 is 93952020112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21102025939 - 2⁵ = 21102025907 is a prime.

It is not a weakly prime, because it can be changed into another prime (21102025933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551012969 + 10551012970.

It is an arithmetic number, because the mean of its divisors is an integer number (10551012970).

Almost surely, 2^21102025939 is an apocalyptic number.

21102025939 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102025939 is an equidigital number, since it uses as much as digits as its factorization.

21102025939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 34.

The spelling of 21102025939 in words is "twenty-one billion, one hundred two million, twenty-five thousand, nine hundred thirty-nine".