18968513 has 2 divisors, whose sum is σ = 18968514. Its totient is φ = 18968512.

The previous prime is 18968489. The next prime is 18968561. The reversal of 18968513 is 31586981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14691889 + 4276624 = 3833^2 + 2068^2 .

It is a cyclic number.

It is not a de Polignac number, because 18968513 - 2⁶ = 18968449 is a prime.

It is not a weakly prime, because it can be changed into another prime (18568513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9484256 + 9484257.

It is an arithmetic number, because the mean of its divisors is an integer number (9484257).

Almost surely, 2^18968513 is an apocalyptic number.

It is an amenable number.

18968513 is a deficient number, since it is larger than the sum of its proper divisors (1).

18968513 is an equidigital number, since it uses as much as digits as its factorization.

18968513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 41.

The square root of 18968513 is about 4355.2856393123. The cubic root of 18968513 is about 266.6926799276.

The spelling of 18968513 in words is "eighteen million, nine hundred sixty-eight thousand, five hundred thirteen".