640572537 has 8 divisors (see below), whose sum is σ = 931741920. Its totient is φ = 388225760.

The previous prime is 640572523. The next prime is 640572539. The reversal of 640572537 is 735275046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 640572537 - 2⁴ = 640572521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 640572495 and 640572504.

It is not an unprimeable number, because it can be changed into a prime (640572539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9705612 + ... + 9705677.

It is an arithmetic number, because the mean of its divisors is an integer number (116467740).

Almost surely, 2^640572537 is an apocalyptic number.

It is an amenable number.

640572537 is a deficient number, since it is larger than the sum of its proper divisors (291169383).

640572537 is a wasteful number, since it uses less digits than its factorization.

640572537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19411303.

The product of its (nonzero) digits is 176400, while the sum is 39.

The square root of 640572537 is about 25309.5345077700. The cubic root of 640572537 is about 862.0307772489.

The spelling of 640572537 in words is "six hundred forty million, five hundred seventy-two thousand, five hundred thirty-seven".