225640881 has 24 divisors (see below), whose sum is σ = 347203584. Its totient is φ = 140714880.

The previous prime is 225640873. The next prime is 225640897. The reversal of 225640881 is 188046522.

225640881 is a `hidden beast` number, since 2 + 2 + 5 + 640 + 8 + 8 + 1 = 666.

It is not a de Polignac number, because 225640881 - 2³ = 225640873 is a prime.

It is a super-2 number, since 2×225640881² = 101827614356912322, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (225640861) 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 23 ways as a sum of consecutive naturals, for example, 21136 + ... + 29966.

It is an arithmetic number, because the mean of its divisors is an integer number (14466816).

Almost surely, 2^225640881 is an apocalyptic number.

It is an amenable number.

225640881 is a deficient number, since it is larger than the sum of its proper divisors (121562703).

225640881 is a wasteful number, since it uses less digits than its factorization.

225640881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9021 (or 9018 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 225640881 is about 15021.3475094613. The cubic root of 225640881 is about 608.7971288320.

The spelling of 225640881 in words is "two hundred twenty-five million, six hundred forty thousand, eight hundred eighty-one".