91890263 has 2 divisors, whose sum is σ = 91890264. Its totient is φ = 91890262.

The previous prime is 91890257. The next prime is 91890329. The reversal of 91890263 is 36209819.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91890263 - 2¹² = 91886167 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91890233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45945131 + 45945132.

It is an arithmetic number, because the mean of its divisors is an integer number (45945132).

Almost surely, 2^91890263 is an apocalyptic number.

91890263 is a deficient number, since it is larger than the sum of its proper divisors (1).

91890263 is an equidigital number, since it uses as much as digits as its factorization.

91890263 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 91890263 is about 9585.9409032186. The cubic root of 91890263 is about 451.2561822650.

The spelling of 91890263 in words is "ninety-one million, eight hundred ninety thousand, two hundred sixty-three".