21430751999 has 2 divisors, whose sum is σ = 21430752000. Its totient is φ = 21430751998.

The previous prime is 21430751957. The next prime is 21430752017. The reversal of 21430751999 is 99915703412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21430751999 - 2⁸ = 21430751743 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21430751099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10715375999 + 10715376000.

It is an arithmetic number, because the mean of its divisors is an integer number (10715376000).

Almost surely, 2^21430751999 is an apocalyptic number.

21430751999 is a deficient number, since it is larger than the sum of its proper divisors (1).

21430751999 is an equidigital number, since it uses as much as digits as its factorization.

21430751999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 612360, while the sum is 50.

The spelling of 21430751999 in words is "twenty-one billion, four hundred thirty million, seven hundred fifty-one thousand, nine hundred ninety-nine".