21519192017 has 2 divisors, whose sum is σ = 21519192018. Its totient is φ = 21519192016.

The previous prime is 21519191977. The next prime is 21519192041. The reversal of 21519192017 is 71029191512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20335900816 + 1183291201 = 142604^2 + 34399^2 .

It is a cyclic number.

It is not a de Polignac number, because 21519192017 - 2⁸ = 21519191761 is a prime.

It is not a weakly prime, because it can be changed into another prime (21519192067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10759596008 + 10759596009.

It is an arithmetic number, because the mean of its divisors is an integer number (10759596009).

Almost surely, 2^21519192017 is an apocalyptic number.

It is an amenable number.

21519192017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21519192017 is an equidigital number, since it uses as much as digits as its factorization.

21519192017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11340, while the sum is 38.

The spelling of 21519192017 in words is "twenty-one billion, five hundred nineteen million, one hundred ninety-two thousand, seventeen".