21430751827 has 2 divisors, whose sum is σ = 21430751828. Its totient is φ = 21430751826.

The previous prime is 21430751809. The next prime is 21430751843. The reversal of 21430751827 is 72815703412.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21430751827 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21430751827.

It is not a weakly prime, because it can be changed into another prime (21430751527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10715375913 + 10715375914.

It is an arithmetic number, because the mean of its divisors is an integer number (10715375914).

Almost surely, 2^21430751827 is an apocalyptic number.

21430751827 is a deficient number, since it is larger than the sum of its proper divisors (1).

21430751827 is an equidigital number, since it uses as much as digits as its factorization.

21430751827 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 94080, while the sum is 40.

The spelling of 21430751827 in words is "twenty-one billion, four hundred thirty million, seven hundred fifty-one thousand, eight hundred twenty-seven".