91923391 has 8 divisors (see below), whose sum is σ = 105601184. Its totient is φ = 78382080.

The previous prime is 91923371. The next prime is 91923407. The reversal of 91923391 is 19332919.

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

It is not a de Polignac number, because 91923391 - 2¹¹ = 91921343 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91923391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91923371) 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, 32670 + ... + 35371.

It is an arithmetic number, because the mean of its divisors is an integer number (13200148).

Almost surely, 2^91923391 is an apocalyptic number.

91923391 is a deficient number, since it is larger than the sum of its proper divisors (13677793).

91923391 is a wasteful number, since it uses less digits than its factorization.

91923391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68241.

The product of its digits is 13122, while the sum is 37.

The square root of 91923391 is about 9587.6686947349. The cubic root of 91923391 is about 451.3104042547.

It can be divided in two parts, 919 and 23391, that added together give a triangular number (24310 = T₂₂₀).

The spelling of 91923391 in words is "ninety-one million, nine hundred twenty-three thousand, three hundred ninety-one".