664057 has 4 divisors (see below), whose sum is σ = 666000. Its totient is φ = 662116.

The previous prime is 664043. The next prime is 664061. The reversal of 664057 is 750466.

664057 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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: 750466 = 2 ⋅375233.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664067) 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, 307 + ... + 1192.

It is an arithmetic number, because the mean of its divisors is an integer number (166500).

2⁶⁶⁴⁰⁵⁷ is an apocalyptic number.

It is an amenable number.

664057 is a deficient number, since it is larger than the sum of its proper divisors (1943).

664057 is a wasteful number, since it uses less digits than its factorization.

664057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1942.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 664057 is about 814.8969259974. The cubic root of 664057 is about 87.2439097234.

It can be divided in two parts, 66 and 4057, that multiplied together give a palindrome (267762).

The spelling of 664057 in words is "six hundred sixty-four thousand, fifty-seven".