644266094 has 4 divisors (see below), whose sum is σ = 966399144. Its totient is φ = 322133046.

The previous prime is 644266069. The next prime is 644266151. The reversal of 644266094 is 490662446.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161066522 + ... + 161066525.

It is an arithmetic number, because the mean of its divisors is an integer number (241599786).

Almost surely, 2^644266094 is an apocalyptic number.

644266094 is a deficient number, since it is larger than the sum of its proper divisors (322133050).

644266094 is a wasteful number, since it uses less digits than its factorization.

644266094 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322133049.

The product of its (nonzero) digits is 248832, while the sum is 41.

The square root of 644266094 is about 25382.3973257059. The cubic root of 644266094 is about 863.6844331891.

The spelling of 644266094 in words is "six hundred forty-four million, two hundred sixty-six thousand, ninety-four".