64642519 has 2 divisors, whose sum is σ = 64642520. Its totient is φ = 64642518.

The previous prime is 64642511. The next prime is 64642549. The reversal of 64642519 is 91524646.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64642519 - 2³ = 64642511 is a prime.

It is a super-2 number, since 2×64642519² = 8357310525330722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64642511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32321259 + 32321260.

It is an arithmetic number, because the mean of its divisors is an integer number (32321260).

Almost surely, 2^64642519 is an apocalyptic number.

64642519 is a deficient number, since it is larger than the sum of its proper divisors (1).

64642519 is an equidigital number, since it uses as much as digits as its factorization.

64642519 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 37.

The square root of 64642519 is about 8040.0571515382. The cubic root of 64642519 is about 401.3341265687.

The spelling of 64642519 in words is "sixty-four million, six hundred forty-two thousand, five hundred nineteen".