225166681 has 2 divisors, whose sum is σ = 225166682. Its totient is φ = 225166680.

The previous prime is 225166651. The next prime is 225166703. The reversal of 225166681 is 186661522.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 193627225 + 31539456 = 13915^2 + 5616^2 .

It is a cyclic number.

It is not a de Polignac number, because 225166681 - 2¹¹ = 225164633 is a prime.

It is a super-2 number, since 2×225166681² = 101400068465111522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 225166681.

It is not a weakly prime, because it can be changed into another prime (225166621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112583340 + 112583341.

It is an arithmetic number, because the mean of its divisors is an integer number (112583341).

Almost surely, 2^225166681 is an apocalyptic number.

It is an amenable number.

225166681 is a deficient number, since it is larger than the sum of its proper divisors (1).

225166681 is an equidigital number, since it uses as much as digits as its factorization.

225166681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 37.

The square root of 225166681 is about 15005.5550047307. Note that the first 3 decimals coincide. The cubic root of 225166681 is about 608.3703532276.

The spelling of 225166681 in words is "two hundred twenty-five million, one hundred sixty-six thousand, six hundred eighty-one".