557809861 has 4 divisors (see below), whose sum is σ = 637496992. Its totient is φ = 478122732.

The previous prime is 557809829. The next prime is 557809871. The reversal of 557809861 is 168908755.

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: 168908755 = 5 ⋅33781751.

It is a cyclic number.

It is not a de Polignac number, because 557809861 - 2⁵ = 557809829 is a prime.

It is a super-2 number, since 2×557809861² = 622303682057678642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (557809801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39843555 + ... + 39843568.

It is an arithmetic number, because the mean of its divisors is an integer number (159374248).

Almost surely, 2^557809861 is an apocalyptic number.

It is an amenable number.

557809861 is a deficient number, since it is larger than the sum of its proper divisors (79687131).

557809861 is an equidigital number, since it uses as much as digits as its factorization.

557809861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79687130.

The product of its (nonzero) digits is 604800, while the sum is 49.

The square root of 557809861 is about 23617.9986662715. The cubic root of 557809861 is about 823.1811099229.

The spelling of 557809861 in words is "five hundred fifty-seven million, eight hundred nine thousand, eight hundred sixty-one".