644052212 has 12 divisors (see below), whose sum is σ = 1128132096. Its totient is φ = 321728760.

The previous prime is 644052197. The next prime is 644052217. The reversal of 644052212 is 212250446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644052217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69428 + ... + 78155.

It is an arithmetic number, because the mean of its divisors is an integer number (94011008).

Almost surely, 2^644052212 is an apocalyptic number.

It is an amenable number.

644052212 is a deficient number, since it is larger than the sum of its proper divisors (484079884).

644052212 is a wasteful number, since it uses less digits than its factorization.

644052212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148678 (or 148676 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 644052212 is about 25378.1837805624. The cubic root of 644052212 is about 863.5888479430.

The spelling of 644052212 in words is "six hundred forty-four million, fifty-two thousand, two hundred twelve".