90564181 has 2 divisors, whose sum is σ = 90564182. Its totient is φ = 90564180.

The previous prime is 90564169. The next prime is 90564191. The reversal of 90564181 is 18146509.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51251281 + 39312900 = 7159^2 + 6270^2 .

It is an emirp because it is prime and its reverse (18146509) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90564181 - 2⁷ = 90564053 is a prime.

It is a super-2 number, since 2×90564181² = 16403741760401522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90564161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45282090 + 45282091.

It is an arithmetic number, because the mean of its divisors is an integer number (45282091).

Almost surely, 2^90564181 is an apocalyptic number.

It is an amenable number.

90564181 is a deficient number, since it is larger than the sum of its proper divisors (1).

90564181 is an equidigital number, since it uses as much as digits as its factorization.

90564181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 90564181 is about 9516.5214758335. The cubic root of 90564181 is about 449.0749408231.

The spelling of 90564181 in words is "ninety million, five hundred sixty-four thousand, one hundred eighty-one".