90809171 has 4 divisors (see below), whose sum is σ = 90933792. Its totient is φ = 90684552.

The previous prime is 90809161. The next prime is 90809177. The reversal of 90809171 is 17190809.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17190809 = 2039 ⋅8431.

It is a cyclic number.

It is not a de Polignac number, because 90809171 - 2¹⁰ = 90808147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90809177) 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, 61211 + ... + 62676.

It is an arithmetic number, because the mean of its divisors is an integer number (22733448).

Almost surely, 2^90809171 is an apocalyptic number.

90809171 is a deficient number, since it is larger than the sum of its proper divisors (124621).

90809171 is a wasteful number, since it uses less digits than its factorization.

90809171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124620.

The product of its (nonzero) digits is 4536, while the sum is 35.

The square root of 90809171 is about 9529.3846076229. The cubic root of 90809171 is about 449.4795150944.

The spelling of 90809171 in words is "ninety million, eight hundred nine thousand, one hundred seventy-one".