91921161 has 8 divisors (see below), whose sum is σ = 124113280. Its totient is φ = 60504912.

The previous prime is 91921157. The next prime is 91921163. The reversal of 91921161 is 16112919.

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

It is not a de Polignac number, because 91921161 - 2² = 91921157 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91921163) 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, 193690 + ... + 194163.

It is an arithmetic number, because the mean of its divisors is an integer number (15514160).

Almost surely, 2^91921161 is an apocalyptic number.

It is an amenable number.

91921161 is a deficient number, since it is larger than the sum of its proper divisors (32192119).

91921161 is a wasteful number, since it uses less digits than its factorization.

91921161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387935.

The product of its digits is 972, while the sum is 30.

The square root of 91921161 is about 9587.5523988138. The cubic root of 91921161 is about 451.3067547290.

The spelling of 91921161 in words is "ninety-one million, nine hundred twenty-one thousand, one hundred sixty-one".