91940191 has 8 divisors (see below), whose sum is σ = 105448064. Its totient is φ = 78525720.

The previous prime is 91940129. The next prime is 91940197. The reversal of 91940191 is 19104919.

It is a happy number.

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

It is not a de Polignac number, because 91940191 - 2¹³ = 91931999 is a prime.

It is a super-2 number, since 2×91940191² = 16905997442232962, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91940197) 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, 21225 + ... + 25186.

It is an arithmetic number, because the mean of its divisors is an integer number (13181008).

Almost surely, 2^91940191 is an apocalyptic number.

91940191 is a deficient number, since it is larger than the sum of its proper divisors (13507873).

91940191 is a wasteful number, since it uses less digits than its factorization.

91940191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46701.

The product of its (nonzero) digits is 2916, while the sum is 34.

The square root of 91940191 is about 9588.5447801009. The cubic root of 91940191 is about 451.3378965425.

The spelling of 91940191 in words is "ninety-one million, nine hundred forty thousand, one hundred ninety-one".