21512311319 has 2 divisors, whose sum is σ = 21512311320. Its totient is φ = 21512311318.

The previous prime is 21512311237. The next prime is 21512311321. The reversal of 21512311319 is 91311321512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21512311319 - 2⁸ = 21512311063 is a prime.

It is a super-2 number, since 2×21512311319² (a number of 21 digits) contains 22 as substring.

Together with 21512311321, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21512311291 and 21512311300.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21512311339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10756155659 + 10756155660.

It is an arithmetic number, because the mean of its divisors is an integer number (10756155660).

Almost surely, 2^21512311319 is an apocalyptic number.

21512311319 is a deficient number, since it is larger than the sum of its proper divisors (1).

21512311319 is an equidigital number, since it uses as much as digits as its factorization.

21512311319 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1620, while the sum is 29.

The spelling of 21512311319 in words is "twenty-one billion, five hundred twelve million, three hundred eleven thousand, three hundred nineteen".