557776561 has 4 divisors (see below), whose sum is σ = 557858800. Its totient is φ = 557694324.

The previous prime is 557776547. The next prime is 557776631. The reversal of 557776561 is 165677755.

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: 165677755 = 5 ⋅33135551.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-557776561 is a prime.

It is a super-2 number, since 2×557776561² = 622229384001973442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (557776061) 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, 29931 + ... + 44848.

It is an arithmetic number, because the mean of its divisors is an integer number (139464700).

Almost surely, 2^557776561 is an apocalyptic number.

It is an amenable number.

557776561 is a deficient number, since it is larger than the sum of its proper divisors (82239).

557776561 is an equidigital number, since it uses as much as digits as its factorization.

557776561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82238.

The product of its digits is 1543500, while the sum is 49.

The square root of 557776561 is about 23617.2936849250. The cubic root of 557776561 is about 823.1647289071.

The spelling of 557776561 in words is "five hundred fifty-seven million, seven hundred seventy-six thousand, five hundred sixty-one".