64239491 has 2 divisors, whose sum is σ = 64239492. Its totient is φ = 64239490.

The previous prime is 64239479. The next prime is 64239493. The reversal of 64239491 is 19493246.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64239491 is a prime.

Together with 64239493, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (64239493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32119745 + 32119746.

It is an arithmetic number, because the mean of its divisors is an integer number (32119746).

Almost surely, 2^64239491 is an apocalyptic number.

64239491 is a deficient number, since it is larger than the sum of its proper divisors (1).

64239491 is an equidigital number, since it uses as much as digits as its factorization.

64239491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 38.

The square root of 64239491 is about 8014.9542107239. The cubic root of 64239491 is about 400.4983185222.

The spelling of 64239491 in words is "sixty-four million, two hundred thirty-nine thousand, four hundred ninety-one".