644151252 has 12 divisors (see below), whose sum is σ = 1503019616. Its totient is φ = 214717080.

The previous prime is 644151251. The next prime is 644151253. The reversal of 644151252 is 252151446.

It is an interprime number because it is at equal distance from previous prime (644151251) and next prime (644151253).

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644151251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26839624 + ... + 26839647.

Almost surely, 2^644151252 is an apocalyptic number.

It is an amenable number.

644151252 is an abundant number, since it is smaller than the sum of its proper divisors (858868364).

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

644151252 is a wasteful number, since it uses less digits than its factorization.

644151252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53679278 (or 53679276 counting only the distinct ones).

The product of its digits is 9600, while the sum is 30.

The square root of 644151252 is about 25380.1349878207. The cubic root of 644151252 is about 863.6331121885.

The spelling of 644151252 in words is "six hundred forty-four million, one hundred fifty-one thousand, two hundred fifty-two".