664042513 has 4 divisors (see below), whose sum is σ = 665627760. Its totient is φ = 662457268.

The previous prime is 664042501. The next prime is 664042517. The reversal of 664042513 is 315240466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 315240466 = 2 ⋅157620233.

It is a cyclic number.

It is not a de Polignac number, because 664042513 - 2²⁵ = 630488081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664042517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 791995 + ... + 792832.

It is an arithmetic number, because the mean of its divisors is an integer number (166406940).

Almost surely, 2^664042513 is an apocalyptic number.

It is an amenable number.

664042513 is a deficient number, since it is larger than the sum of its proper divisors (1585247).

664042513 is a wasteful number, since it uses less digits than its factorization.

664042513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1585246.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 664042513 is about 25769.0223524293. The cubic root of 664042513 is about 872.4327528405.

Adding to 664042513 its reverse (315240466), we get a palindrome (979282979).

The spelling of 664042513 in words is "six hundred sixty-four million, forty-two thousand, five hundred thirteen".