91907081 has 8 divisors (see below), whose sum is σ = 105967104. Its totient is φ = 78079680.

The previous prime is 91907077. The next prime is 91907087. The reversal of 91907081 is 18070919.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 91907081 - 2² = 91907077 is a prime.

It is a super-2 number, since 2×91907081² = 16893823075881122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91907087) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57305 + ... + 58886.

It is an arithmetic number, because the mean of its divisors is an integer number (13245888).

Almost surely, 2^91907081 is an apocalyptic number.

It is an amenable number.

91907081 is a deficient number, since it is larger than the sum of its proper divisors (14060023).

91907081 is a wasteful number, since it uses less digits than its factorization.

91907081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116311.

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

The square root of 91907081 is about 9586.8180852669. The cubic root of 91907081 is about 451.2837106207.

The spelling of 91907081 in words is "ninety-one million, nine hundred seven thousand, eighty-one".