644647342 has 8 divisors (see below), whose sum is σ = 967473000. Its totient is φ = 322156344.

The previous prime is 644647313. The next prime is 644647363. The reversal of 644647342 is 243746446.

644647342 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 644647295 and 644647304.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78792 + ... + 86587.

It is an arithmetic number, because the mean of its divisors is an integer number (120934125).

Almost surely, 2^644647342 is an apocalyptic number.

644647342 is a deficient number, since it is larger than the sum of its proper divisors (322825658).

644647342 is a wasteful number, since it uses less digits than its factorization.

644647342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167330.

The product of its digits is 387072, while the sum is 40.

The square root of 644647342 is about 25389.9063015207. The cubic root of 644647342 is about 863.8547629315.

The spelling of 644647342 in words is "six hundred forty-four million, six hundred forty-seven thousand, three hundred forty-two".