91157665 has 8 divisors (see below), whose sum is σ = 110357928. Its totient is φ = 72280320.

The previous prime is 91157663. The next prime is 91157683. The reversal of 91157665 is 56675119.

It can be written as a sum of positive squares in 4 ways, for example, as 4276624 + 86881041 = 2068^2 + 9321^2 .

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

It is not a de Polignac number, because 91157665 - 2¹ = 91157663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91157663) 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, 80106 + ... + 81235.

It is an arithmetic number, because the mean of its divisors is an integer number (13794741).

Almost surely, 2^91157665 is an apocalyptic number.

It is an amenable number.

91157665 is a deficient number, since it is larger than the sum of its proper divisors (19200263).

91157665 is a wasteful number, since it uses less digits than its factorization.

91157665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161459.

The product of its digits is 56700, while the sum is 40.

The square root of 91157665 is about 9547.6523292378. The cubic root of 91157665 is about 450.0537631238.

The spelling of 91157665 in words is "ninety-one million, one hundred fifty-seven thousand, six hundred sixty-five".