91511601 has 4 divisors (see below), whose sum is σ = 122015472. Its totient is φ = 61007732.

The previous prime is 91511599. The next prime is 91511627. The reversal of 91511601 is 10611519.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91511601 - 2¹ = 91511599 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91511671) 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, 15251931 + ... + 15251936.

It is an arithmetic number, because the mean of its divisors is an integer number (30503868).

Almost surely, 2^91511601 is an apocalyptic number.

It is an amenable number.

91511601 is a deficient number, since it is larger than the sum of its proper divisors (30503871).

91511601 is a wasteful number, since it uses less digits than its factorization.

91511601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30503870.

The product of its (nonzero) digits is 270, while the sum is 24.

The square root of 91511601 is about 9566.1696096191. The cubic root of 91511601 is about 450.6354824069.

The spelling of 91511601 in words is "ninety-one million, five hundred eleven thousand, six hundred one".