561990831 has 8 divisors (see below), whose sum is σ = 749493120. Its totient is φ = 374574552.

The previous prime is 561990791. The next prime is 561990859. The reversal of 561990831 is 138099165.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 561990831 - 2¹⁰ = 561989807 is a prime.

It is a super-2 number, since 2×561990831² = 631667388256141122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561990881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4285 + ... + 33798.

It is an arithmetic number, because the mean of its divisors is an integer number (93686640).

Almost surely, 2^561990831 is an apocalyptic number.

561990831 is a deficient number, since it is larger than the sum of its proper divisors (187502289).

561990831 is a wasteful number, since it uses less digits than its factorization.

561990831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43005.

The product of its (nonzero) digits is 58320, while the sum is 42.

The square root of 561990831 is about 23706.3457960100. The cubic root of 561990831 is about 825.2326645895.

The spelling of 561990831 in words is "five hundred sixty-one million, nine hundred ninety thousand, eight hundred thirty-one".