91919291 has 4 divisors (see below), whose sum is σ = 92008800. Its totient is φ = 91829784.

The previous prime is 91919279. The next prime is 91919327. The reversal of 91919291 is 19291919.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91919291 - 2¹⁸ = 91657147 is a prime.

It is a super-3 number, since 3×91919291³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91919231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43196 + ... + 45273.

It is an arithmetic number, because the mean of its divisors is an integer number (23002200).

Almost surely, 2^91919291 is an apocalyptic number.

91919291 is a deficient number, since it is larger than the sum of its proper divisors (89509).

91919291 is a wasteful number, since it uses less digits than its factorization.

91919291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89508.

The product of its digits is 13122, while the sum is 41.

The square root of 91919291 is about 9587.4548760346. The cubic root of 91919291 is about 451.3036943189.

The spelling of 91919291 in words is "ninety-one million, nine hundred nineteen thousand, two hundred ninety-one".