643507260 has 48 divisors (see below), whose sum is σ = 1965624192. Its totient is φ = 156001600.

The previous prime is 643507253. The next prime is 643507301. The reversal of 643507260 is 62705346.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 486846 + ... + 488165.

It is an arithmetic number, because the mean of its divisors is an integer number (40950504).

Almost surely, 2^643507260 is an apocalyptic number.

643507260 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

643507260 is an abundant number, since it is smaller than the sum of its proper divisors (1322116932).

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

643507260 is a wasteful number, since it uses less digits than its factorization.

643507260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 975034 (or 975032 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 33.

The square root of 643507260 is about 25367.4448851279. Note that the first 3 decimals coincide. The cubic root of 643507260 is about 863.3452096907.

The spelling of 643507260 in words is "six hundred forty-three million, five hundred seven thousand, two hundred sixty".