225210861 has 20 divisors (see below), whose sum is σ = 337258944. Its totient is φ = 149769000.

The previous prime is 225210773. The next prime is 225210889. The reversal of 225210861 is 168012522.

It is a happy number.

It is not a de Polignac number, because 225210861 - 2¹⁰ = 225209837 is a prime.

It is a super-2 number, since 2×225210861² = 101439863824722642, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225210061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 31686 + ... + 38136.

Almost surely, 2^225210861 is an apocalyptic number.

It is an amenable number.

225210861 is a deficient number, since it is larger than the sum of its proper divisors (112048083).

225210861 is an equidigital number, since it uses as much as digits as its factorization.

225210861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6894 (or 6885 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 225210861 is about 15007.0270540171. The cubic root of 225210861 is about 608.4101401155.

The spelling of 225210861 in words is "two hundred twenty-five million, two hundred ten thousand, eight hundred sixty-one".