644361224 has 16 divisors (see below), whose sum is σ = 1301114220. Its totient is φ = 297397440.

The previous prime is 644361199. The next prime is 644361233. The reversal of 644361224 is 422163446.

It can be written as a sum of positive squares in 2 ways, for example, as 628504900 + 15856324 = 25070^2 + 3982^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3097787 + ... + 3097994.

Almost surely, 2^644361224 is an apocalyptic number.

It is an amenable number.

644361224 is an abundant number, since it is smaller than the sum of its proper divisors (656752996).

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

644361224 is a wasteful number, since it uses less digits than its factorization.

644361224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6195800 (or 6195796 counting only the distinct ones).

The product of its digits is 27648, while the sum is 32.

The square root of 644361224 is about 25384.2711930045. The cubic root of 644361224 is about 863.7269406030.

The spelling of 644361224 in words is "six hundred forty-four million, three hundred sixty-one thousand, two hundred twenty-four".