21113680639 has 2 divisors, whose sum is σ = 21113680640. Its totient is φ = 21113680638.

The previous prime is 21113680613. The next prime is 21113680657. The reversal of 21113680639 is 93608631112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21113680639 - 2¹⁵ = 21113647871 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21113680739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556840319 + 10556840320.

It is an arithmetic number, because the mean of its divisors is an integer number (10556840320).

Almost surely, 2^21113680639 is an apocalyptic number.

21113680639 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113680639 is an equidigital number, since it uses as much as digits as its factorization.

21113680639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 40.

The spelling of 21113680639 in words is "twenty-one billion, one hundred thirteen million, six hundred eighty thousand, six hundred thirty-nine".