21300021959 has 2 divisors, whose sum is σ = 21300021960. Its totient is φ = 21300021958.

The previous prime is 21300021943. The next prime is 21300022001. The reversal of 21300021959 is 95912000312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21300021959 - 2⁴ = 21300021943 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21300021929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650010979 + 10650010980.

It is an arithmetic number, because the mean of its divisors is an integer number (10650010980).

Almost surely, 2^21300021959 is an apocalyptic number.

21300021959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21300021959 is an equidigital number, since it uses as much as digits as its factorization.

21300021959 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4860, while the sum is 32.

The spelling of 21300021959 in words is "twenty-one billion, three hundred million, twenty-one thousand, nine hundred fifty-nine".