561277644 has 24 divisors (see below), whose sum is σ = 1386686448. Its totient is φ = 176087040.

The previous prime is 561277637. The next prime is 561277663. The reversal of 561277644 is 446772165.

It is a junction number, because it is equal to n+sod(n) for n = 561277596 and 561277605.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1375477 + ... + 1375884.

It is an arithmetic number, because the mean of its divisors is an integer number (57778602).

Almost surely, 2^561277644 is an apocalyptic number.

It is an amenable number.

561277644 is an abundant number, since it is smaller than the sum of its proper divisors (825408804).

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

561277644 is a wasteful number, since it uses less digits than its factorization.

561277644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2751385 (or 2751383 counting only the distinct ones).

The product of its digits is 282240, while the sum is 42.

The square root of 561277644 is about 23691.2989090932. The cubic root of 561277644 is about 824.8834333012.

The spelling of 561277644 in words is "five hundred sixty-one million, two hundred seventy-seven thousand, six hundred forty-four".