644262212 has 24 divisors (see below), whose sum is σ = 1269633792. Its totient is φ = 283399200.

The previous prime is 644262211. The next prime is 644262221. The reversal of 644262212 is 212262446.

It is a super-2 number, since 2×644262212² = 830147595622265888, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (644262211) 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 7 ways as a sum of consecutive naturals, for example, 234803 + ... + 237530.

It is an arithmetic number, because the mean of its divisors is an integer number (52901408).

Almost surely, 2^644262212 is an apocalyptic number.

644262212 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

644262212 is a deficient number, since it is larger than the sum of its proper divisors (625371580).

644262212 is a wasteful number, since it uses less digits than its factorization.

644262212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472379 (or 472377 counting only the distinct ones).

The product of its digits is 9216, while the sum is 29.

The square root of 644262212 is about 25382.3208552725. The cubic root of 644262212 is about 863.6826984868.

The spelling of 644262212 in words is "six hundred forty-four million, two hundred sixty-two thousand, two hundred twelve".