91087236 has 18 divisors (see below), whose sum is σ = 230248382. Its totient is φ = 30362400.

The previous prime is 91087219. The next prime is 91087247. The reversal of 91087236 is 63278019.

It can be written as a sum of positive squares in only one way, i.e., 47527236 + 43560000 = 6894^2 + 6600^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 2530201 = 91087236 / (9 + 1 + 0 + 8 + 7 + 2 + 3 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 91087236.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1265065 + ... + 1265136.

Almost surely, 2^91087236 is an apocalyptic number.

It is an amenable number.

91087236 is an abundant number, since it is smaller than the sum of its proper divisors (139161146).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91087236 is a wasteful number, since it uses less digits than its factorization.

91087236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2530211 (or 2530206 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 91087236 is about 9543.9633276747. The cubic root of 91087236 is about 449.9378284479.

The spelling of 91087236 in words is "ninety-one million, eighty-seven thousand, two hundred thirty-six".