644026414 has 4 divisors (see below), whose sum is σ = 966039624. Its totient is φ = 322013206.

The previous prime is 644026387. The next prime is 644026423. The reversal of 644026414 is 414620446.

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, 161006602 + ... + 161006605.

It is an arithmetic number, because the mean of its divisors is an integer number (241509906).

Almost surely, 2^644026414 is an apocalyptic number.

644026414 is a deficient number, since it is larger than the sum of its proper divisors (322013210).

644026414 is a wasteful number, since it uses less digits than its factorization.

644026414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322013209.

The product of its (nonzero) digits is 18432, while the sum is 31.

The square root of 644026414 is about 25377.6755042695. The cubic root of 644026414 is about 863.5773172202.

The spelling of 644026414 in words is "six hundred forty-four million, twenty-six thousand, four hundred fourteen".