644702354 has 8 divisors (see below), whose sum is σ = 989543280. Its totient is φ = 314854596.

The previous prime is 644702353. The next prime is 644702363. The reversal of 644702354 is 453207446.

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

It is a super-2 number, since 2×644702354² = 831282250506282632, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (644702353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3748184 + ... + 3748355.

It is an arithmetic number, because the mean of its divisors is an integer number (123692910).

Almost surely, 2^644702354 is an apocalyptic number.

644702354 is a deficient number, since it is larger than the sum of its proper divisors (344840926).

644702354 is a wasteful number, since it uses less digits than its factorization.

644702354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7496584.

The product of its (nonzero) digits is 80640, while the sum is 35.

The square root of 644702354 is about 25390.9896223050. The cubic root of 644702354 is about 863.8793350365.

The spelling of 644702354 in words is "six hundred forty-four million, seven hundred two thousand, three hundred fifty-four".