644341512 has 32 divisors (see below), whose sum is σ = 1627466400. Its totient is φ = 212565504.

The previous prime is 644341507. The next prime is 644341513. The reversal of 644341512 is 215143446.

It is a super-2 number, since 2×644341512² = 830351968172892288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 644341512.

It is not an unprimeable number, because it can be changed into a prime (644341513) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136062 + ... + 140717.

It is an arithmetic number, because the mean of its divisors is an integer number (50858325).

Almost surely, 2^644341512 is an apocalyptic number.

It is an amenable number.

644341512 is an abundant number, since it is smaller than the sum of its proper divisors (983124888).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644341512 is a wasteful number, since it uses less digits than its factorization.

644341512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276885 (or 276881 counting only the distinct ones).

The product of its digits is 11520, while the sum is 30.

The square root of 644341512 is about 25383.8829181038. The cubic root of 644341512 is about 863.7181329351.

Adding to 644341512 its reverse (215143446), we get a palindrome (859484958).

The spelling of 644341512 in words is "six hundred forty-four million, three hundred forty-one thousand, five hundred twelve".