561167881 has 4 divisors (see below), whose sum is σ = 565205200. Its totient is φ = 557130564.

The previous prime is 561167879. The next prime is 561167903. The reversal of 561167881 is 188761165.

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.

It is a cyclic number.

It is not a de Polignac number, because 561167881 - 2¹ = 561167879 is a prime.

It is a super-2 number, since 2×561167881² = 629818781332060322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561164881) 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, 2018451 + ... + 2018728.

It is an arithmetic number, because the mean of its divisors is an integer number (141301300).

Almost surely, 2^561167881 is an apocalyptic number.

It is an amenable number.

561167881 is a deficient number, since it is larger than the sum of its proper divisors (4037319).

561167881 is a wasteful number, since it uses less digits than its factorization.

561167881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4037318.

The product of its digits is 80640, while the sum is 43.

The square root of 561167881 is about 23688.9822702454. The cubic root of 561167881 is about 824.8296586176.

The spelling of 561167881 in words is "five hundred sixty-one million, one hundred sixty-seven thousand, eight hundred eighty-one".