644530052 has 12 divisors (see below), whose sum is σ = 1164312576. Its totient is φ = 311869320.

The previous prime is 644530049. The next prime is 644530057. The reversal of 644530052 is 250035446.

It is a super-2 number, since 2×644530052² = 830837975862245408, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 644529997 and 644530024.

It is not an unprimeable number, because it can be changed into a prime (644530057) 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, 2598788 + ... + 2599035.

It is an arithmetic number, because the mean of its divisors is an integer number (97026048).

Almost surely, 2^644530052 is an apocalyptic number.

644530052 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

644530052 is a deficient number, since it is larger than the sum of its proper divisors (519782524).

644530052 is a wasteful number, since it uses less digits than its factorization.

644530052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5197858 (or 5197856 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 29.

The square root of 644530052 is about 25387.5964202994. The cubic root of 644530052 is about 863.8023685632.

Adding to 644530052 its reverse (250035446), we get a palindrome (894565498).

The spelling of 644530052 in words is "six hundred forty-four million, five hundred thirty thousand, fifty-two".