643137472 has 56 divisors (see below), whose sum is σ = 1380158784. Its totient is φ = 296189952.

The previous prime is 643137463. The next prime is 643137487. The reversal of 643137472 is 274731346.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44848 + ... + 57424.

Almost surely, 2^643137472 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643137472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (690079392).

643137472 is an abundant number, since it is smaller than the sum of its proper divisors (737021312).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643137472 is a wasteful number, since it uses less digits than its factorization.

643137472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12653 (or 12643 counting only the distinct ones).

The product of its digits is 84672, while the sum is 37.

The square root of 643137472 is about 25360.1552045724. The cubic root of 643137472 is about 863.1798057704.

The spelling of 643137472 in words is "six hundred forty-three million, one hundred thirty-seven thousand, four hundred seventy-two".