561128957 has 4 divisors (see below), whose sum is σ = 590662080. Its totient is φ = 531595836.

The previous prime is 561128947. The next prime is 561128963. The reversal of 561128957 is 759821165.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 759821165 = 5 ⋅151964233.

It is a cyclic number.

It is not a de Polignac number, because 561128957 - 2⁴ = 561128941 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561128947) 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, 14766533 + ... + 14766570.

It is an arithmetic number, because the mean of its divisors is an integer number (147665520).

Almost surely, 2^561128957 is an apocalyptic number.

It is an amenable number.

561128957 is a deficient number, since it is larger than the sum of its proper divisors (29533123).

561128957 is a wasteful number, since it uses less digits than its factorization.

561128957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29533122.

The product of its digits is 151200, while the sum is 44.

The square root of 561128957 is about 23688.1606926329. The cubic root of 561128957 is about 824.8105874311.

The spelling of 561128957 in words is "five hundred sixty-one million, one hundred twenty-eight thousand, nine hundred fifty-seven".