643712366 has 16 divisors (see below), whose sum is σ = 1057079808. Its totient is φ = 291559800.

The previous prime is 643712351. The next prime is 643712369. The reversal of 643712366 is 663217346.

It is a super-2 number, since 2×643712366² = 828731220282635912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643712369) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45470 + ... + 57921.

It is an arithmetic number, because the mean of its divisors is an integer number (66067488).

Almost surely, 2^643712366 is an apocalyptic number.

643712366 is a deficient number, since it is larger than the sum of its proper divisors (413367442).

643712366 is a wasteful number, since it uses less digits than its factorization.

643712366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103687.

The product of its digits is 108864, while the sum is 38.

The square root of 643712366 is about 25371.4872642500. The cubic root of 643712366 is about 863.4369250365.

The spelling of 643712366 in words is "six hundred forty-three million, seven hundred twelve thousand, three hundred sixty-six".