643437496 has 48 divisors (see below), whose sum is σ = 1312786440. Its totient is φ = 293904000.

The previous prime is 643437467. The next prime is 643437521. The reversal of 643437496 is 694734346.

It is a super-2 number, since 2×643437496² = 828023622517500032, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2563371 + ... + 2563621.

Almost surely, 2^643437496 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 643437496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (656393220).

643437496 is an abundant number, since it is smaller than the sum of its proper divisors (669348944).

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

643437496 is a wasteful number, since it uses less digits than its factorization.

643437496 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 584 (or 423 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 46.

The square root of 643437496 is about 25366.0697783476. The cubic root of 643437496 is about 863.3140095289.

The spelling of 643437496 in words is "six hundred forty-three million, four hundred thirty-seven thousand, four hundred ninety-six".