91091901 has 4 divisors (see below), whose sum is σ = 121455872. Its totient is φ = 60727932.

The previous prime is 91091887. The next prime is 91091921. The reversal of 91091901 is 10919019.

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 not a de Polignac number, because 91091901 - 2⁶ = 91091837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91091921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15181981 + ... + 15181986.

It is an arithmetic number, because the mean of its divisors is an integer number (30363968).

Almost surely, 2^91091901 is an apocalyptic number.

It is an amenable number.

91091901 is a deficient number, since it is larger than the sum of its proper divisors (30363971).

91091901 is a wasteful number, since it uses less digits than its factorization.

91091901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30363970.

The product of its (nonzero) digits is 729, while the sum is 30.

The square root of 91091901 is about 9544.2077198686. The cubic root of 91091901 is about 449.9455094514.

The spelling of 91091901 in words is "ninety-one million, ninety-one thousand, nine hundred one".