643551662 has 24 divisors (see below), whose sum is σ = 1070813520. Its totient is φ = 289773120.

The previous prime is 643551659. The next prime is 643551691. The reversal of 643551662 is 266155346.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9362 + ... + 37077.

It is an arithmetic number, because the mean of its divisors is an integer number (44617230).

Almost surely, 2^643551662 is an apocalyptic number.

643551662 is a deficient number, since it is larger than the sum of its proper divisors (427261858).

643551662 is a wasteful number, since it uses less digits than its factorization.

643551662 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46508 (or 46495 counting only the distinct ones).

The product of its digits is 129600, while the sum is 38.

The square root of 643551662 is about 25368.3200468616. The cubic root of 643551662 is about 863.3650661734.

The spelling of 643551662 in words is "six hundred forty-three million, five hundred fifty-one thousand, six hundred sixty-two".