643742722 has 32 divisors (see below), whose sum is σ = 1179650304. Its totient is φ = 257452800.

The previous prime is 643742719. The next prime is 643742741. The reversal of 643742722 is 227247346.

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, 11179 + ... + 37582.

It is an arithmetic number, because the mean of its divisors is an integer number (36864072).

Almost surely, 2^643742722 is an apocalyptic number.

643742722 is a deficient number, since it is larger than the sum of its proper divisors (535907582).

643742722 is a wasteful number, since it uses less digits than its factorization.

643742722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48834.

The product of its digits is 112896, while the sum is 37.

The square root of 643742722 is about 25372.0854877954. The cubic root of 643742722 is about 863.4504973920.

The spelling of 643742722 in words is "six hundred forty-three million, seven hundred forty-two thousand, seven hundred twenty-two".