644406554463334 has 48 divisors (see below), whose sum is σ = 1056879090888192. Its totient is φ = 294521630274144.

The previous prime is 644406554463271. The next prime is 644406554463367. The reversal of 644406554463334 is 433364455604446.

It is a hoax number, since the sum of its digits (61) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1180722499 + ... + 1181268145.

It is an arithmetic number, because the mean of its divisors is an integer number (22018314393504).

Almost surely, 2^{644406554463334} is an apocalyptic number.

644406554463334 is a deficient number, since it is larger than the sum of its proper divisors (412472536424858).

644406554463334 is a wasteful number, since it uses less digits than its factorization.

644406554463334 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 579701 (or 579688 counting only the distinct ones).

The product of its (nonzero) digits is 597196800, while the sum is 61.

The spelling of 644406554463334 in words is "six hundred forty-four trillion, four hundred six billion, five hundred fifty-four million, four hundred sixty-three thousand, three hundred thirty-four".