225420581 has 2 divisors, whose sum is σ = 225420582. Its totient is φ = 225420580.

The previous prime is 225420553. The next prime is 225420593. The reversal of 225420581 is 185024522.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 186868900 + 38551681 = 13670^2 + 6209^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-225420581 is a prime.

It is a super-2 number, since 2×225420581² = 101628876676755122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (225420511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112710290 + 112710291.

It is an arithmetic number, because the mean of its divisors is an integer number (112710291).

Almost surely, 2^225420581 is an apocalyptic number.

It is an amenable number.

225420581 is a deficient number, since it is larger than the sum of its proper divisors (1).

225420581 is an equidigital number, since it uses as much as digits as its factorization.

225420581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6400, while the sum is 29.

The square root of 225420581 is about 15014.0128213612. The cubic root of 225420581 is about 608.5989353155.

It can be divided in two parts, 225420 and 581, that multiplied together give a triangular number (130969020 = T₁₆₁₈₄).

The spelling of 225420581 in words is "two hundred twenty-five million, four hundred twenty thousand, five hundred eighty-one".