64617491 has 2 divisors, whose sum is σ = 64617492. Its totient is φ = 64617490.

The previous prime is 64617467. The next prime is 64617523. The reversal of 64617491 is 19471646.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64617491 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (64617451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32308745 + 32308746.

It is an arithmetic number, because the mean of its divisors is an integer number (32308746).

Almost surely, 2^64617491 is an apocalyptic number.

64617491 is a deficient number, since it is larger than the sum of its proper divisors (1).

64617491 is an equidigital number, since it uses as much as digits as its factorization.

64617491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 64617491 is about 8038.5005442558. The cubic root of 64617491 is about 401.2823243014.

The spelling of 64617491 in words is "sixty-four million, six hundred seventeen thousand, four hundred ninety-one".