643111216 has 40 divisors (see below), whose sum is σ = 1361323584. Its totient is φ = 291888960.

The previous prime is 643111187. The next prime is 643111229. The reversal of 643111216 is 612111346.

It is a super-2 number, since 2×643111216² = 827184072289997312, which contains 22 as substring.

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, 136191 + ... + 140833.

Almost surely, 2^643111216 is an apocalyptic number.

It is an amenable number.

643111216 is an abundant number, since it is smaller than the sum of its proper divisors (718212368).

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

643111216 is a wasteful number, since it uses less digits than its factorization.

643111216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5449 (or 5443 counting only the distinct ones).

The product of its digits is 864, while the sum is 25.

The square root of 643111216 is about 25359.6375368419. The cubic root of 643111216 is about 863.1680592111.

The spelling of 643111216 in words is "six hundred forty-three million, one hundred eleven thousand, two hundred sixteen".