561997899 has 16 divisors (see below), whose sum is σ = 833763840. Its totient is φ = 374136840.

The previous prime is 561997871. The next prime is 561997913. The reversal of 561997899 is 998799165.

561997899 is a `hidden beast` number, since 5 + 619 + 9 + 7 + 8 + 9 + 9 = 666.

It is not a de Polignac number, because 561997899 - 2⁷ = 561997771 is a prime.

It is not an unprimeable number, because it can be changed into a prime (561997199) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5314 + ... + 33944.

It is an arithmetic number, because the mean of its divisors is an integer number (52110240).

Almost surely, 2^561997899 is an apocalyptic number.

561997899 is a deficient number, since it is larger than the sum of its proper divisors (271765941).

561997899 is a wasteful number, since it uses less digits than its factorization.

561997899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29367 (or 29361 counting only the distinct ones).

The product of its digits is 11022480, while the sum is 63.

The square root of 561997899 is about 23706.4948695500. The cubic root of 561997899 is about 825.2361241477.

The spelling of 561997899 in words is "five hundred sixty-one million, nine hundred ninety-seven thousand, eight hundred ninety-nine".