225610991 has 2 divisors, whose sum is σ = 225610992. Its totient is φ = 225610990.

The previous prime is 225610943. The next prime is 225610999. The reversal of 225610991 is 199016522.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 225610991 - 2¹⁸ = 225348847 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (225610999) 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 as a sum of consecutive naturals, namely, 112805495 + 112805496.

It is an arithmetic number, because the mean of its divisors is an integer number (112805496).

Almost surely, 2^225610991 is an apocalyptic number.

225610991 is a deficient number, since it is larger than the sum of its proper divisors (1).

225610991 is an equidigital number, since it uses as much as digits as its factorization.

225610991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 225610991 is about 15020.3525591113. The cubic root of 225610991 is about 608.7702457754.

The spelling of 225610991 in words is "two hundred twenty-five million, six hundred ten thousand, nine hundred ninety-one".