90250091 has 4 divisors (see below), whose sum is σ = 94174032. Its totient is φ = 86326152.

The previous prime is 90250079. The next prime is 90250109. The reversal of 90250091 is 19005209.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19005209 = 71 ⋅267679.

It is a cyclic number.

It is not a de Polignac number, because 90250091 - 2²² = 86055787 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90250091.

It is not an unprimeable number, because it can be changed into a prime (90250031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1961936 + ... + 1961981.

It is an arithmetic number, because the mean of its divisors is an integer number (23543508).

Almost surely, 2^90250091 is an apocalyptic number.

90250091 is a deficient number, since it is larger than the sum of its proper divisors (3923941).

90250091 is a wasteful number, since it uses less digits than its factorization.

90250091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3923940.

The product of its (nonzero) digits is 810, while the sum is 26.

The square root of 90250091 is about 9500.0047894725. The cubic root of 90250091 is about 448.5551866841. Note that the first 3 decimals are identical.

The spelling of 90250091 in words is "ninety million, two hundred fifty thousand, ninety-one".