91501086491 has 4 divisors (see below), whose sum is σ = 94656296400. Its totient is φ = 88345876584.

The previous prime is 91501086431. The next prime is 91501086511. The reversal of 91501086491 is 19468010519.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19468010519 = 157 ⋅124000067.

It is a cyclic number.

It is not a de Polignac number, because 91501086491 - 2¹⁴ = 91501070107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91501086431) 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, 1577604911 + ... + 1577604968.

It is an arithmetic number, because the mean of its divisors is an integer number (23664074100).

Almost surely, 2^91501086491 is an apocalyptic number.

91501086491 is a deficient number, since it is larger than the sum of its proper divisors (3155209909).

91501086491 is a wasteful number, since it uses less digits than its factorization.

91501086491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3155209908.

The product of its (nonzero) digits is 77760, while the sum is 44.

The spelling of 91501086491 in words is "ninety-one billion, five hundred one million, eighty-six thousand, four hundred ninety-one".