556919991 has 12 divisors (see below), whose sum is σ = 830390080. Its totient is φ = 359303040.

The previous prime is 556919947. The next prime is 556920037. The reversal of 556919991 is 199919655.

It is not a de Polignac number, because 556919991 - 2⁷ = 556919863 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 (556919291) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 997786 + ... + 998343.

Almost surely, 2^556919991 is an apocalyptic number.

556919991 is a deficient number, since it is larger than the sum of its proper divisors (273470089).

556919991 is a wasteful number, since it uses less digits than its factorization.

556919991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1996166 (or 1996163 counting only the distinct ones).

The product of its digits is 984150, while the sum is 54.

The square root of 556919991 is about 23599.1523364717. The cubic root of 556919991 is about 822.7431386706.

The spelling of 556919991 in words is "five hundred fifty-six million, nine hundred nineteen thousand, nine hundred ninety-one".