90185261 has 2 divisors, whose sum is σ = 90185262. Its totient is φ = 90185260.

The previous prime is 90185257. The next prime is 90185269. The reversal of 90185261 is 16258109.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68376361 + 21808900 = 8269^2 + 4670^2 .

It is a cyclic number.

It is not a de Polignac number, because 90185261 - 2² = 90185257 is a prime.

It is a super-3 number, since 3×90185261³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90185269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45092630 + 45092631.

It is an arithmetic number, because the mean of its divisors is an integer number (45092631).

Almost surely, 2^90185261 is an apocalyptic number.

It is an amenable number.

90185261 is a deficient number, since it is larger than the sum of its proper divisors (1).

90185261 is an equidigital number, since it uses as much as digits as its factorization.

90185261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 90185261 is about 9496.5920729491. The cubic root of 90185261 is about 448.4477563268.

The spelling of 90185261 in words is "ninety million, one hundred eighty-five thousand, two hundred sixty-one".