643531037 has 4 divisors (see below), whose sum is σ = 643726656. Its totient is φ = 643335420.

The previous prime is 643531001. The next prime is 643531043. The reversal of 643531037 is 730135346.

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.

It is a cyclic number.

It is not a de Polignac number, because 643531037 - 2¹⁴ = 643514653 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643530994 and 643531012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643531067) 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, 92789 + ... + 99482.

It is an arithmetic number, because the mean of its divisors is an integer number (160931664).

Almost surely, 2^643531037 is an apocalyptic number.

It is an amenable number.

643531037 is a deficient number, since it is larger than the sum of its proper divisors (195619).

643531037 is a wasteful number, since it uses less digits than its factorization.

643531037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195618.

The product of its (nonzero) digits is 22680, while the sum is 32.

The square root of 643531037 is about 25367.9135326499. The cubic root of 643531037 is about 863.3558428296.

The spelling of 643531037 in words is "six hundred forty-three million, five hundred thirty-one thousand, thirty-seven".