643468750 has 56 divisors (see below), whose sum is σ = 1230453000. Its totient is φ = 252300000.

The previous prime is 643468729. The next prime is 643468781. The reversal of 643468750 is 57864346.

It is a junction number, because it is equal to n+sod(n) for n = 643468697 and 643468706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 1843576 + ... + 1843924.

It is an arithmetic number, because the mean of its divisors is an integer number (21972375).

Almost surely, 2^643468750 is an apocalyptic number.

643468750 is a deficient number, since it is larger than the sum of its proper divisors (586984250).

643468750 is an frugal number, since it uses more digits than its factorization.

643468750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440 (or 415 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 43.

The square root of 643468750 is about 25366.6858300409. The cubic root of 643468750 is about 863.3279873586.

The spelling of 643468750 in words is "six hundred forty-three million, four hundred sixty-eight thousand, seven hundred fifty".