21130039979 has 2 divisors, whose sum is σ = 21130039980. Its totient is φ = 21130039978.

The previous prime is 21130039969. The next prime is 21130039991. The reversal of 21130039979 is 97993003112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21130039979 - 2²⁴ = 21113262763 is a prime.

It is not a weakly prime, because it can be changed into another prime (21130039969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565019989 + 10565019990.

It is an arithmetic number, because the mean of its divisors is an integer number (10565019990).

Almost surely, 2^21130039979 is an apocalyptic number.

21130039979 is a deficient number, since it is larger than the sum of its proper divisors (1).

21130039979 is an equidigital number, since it uses as much as digits as its factorization.

21130039979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 91854, while the sum is 44.

The spelling of 21130039979 in words is "twenty-one billion, one hundred thirty million, thirty-nine thousand, nine hundred seventy-nine".