21999022979 has 2 divisors, whose sum is σ = 21999022980. Its totient is φ = 21999022978.

The previous prime is 21999022961. The next prime is 21999023027. The reversal of 21999022979 is 97922099912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21999022979 - 2²⁴ = 21982245763 is a prime.

It is not a weakly prime, because it can be changed into another prime (21999022939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10999511489 + 10999511490.

It is an arithmetic number, because the mean of its divisors is an integer number (10999511490).

Almost surely, 2^21999022979 is an apocalyptic number.

21999022979 is a deficient number, since it is larger than the sum of its proper divisors (1).

21999022979 is an equidigital number, since it uses as much as digits as its factorization.

21999022979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3306744, while the sum is 59.

The spelling of 21999022979 in words is "twenty-one billion, nine hundred ninety-nine million, twenty-two thousand, nine hundred seventy-nine".