91323431 has 4 divisors (see below), whose sum is σ = 91356864. Its totient is φ = 91290000.

The previous prime is 91323391. The next prime is 91323451. The reversal of 91323431 is 13432319.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91323431 is a prime.

It is a super-2 number, since 2×91323431² = 16679938099223522, which contains 22 as substring.

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 91323431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91323451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12215 + ... + 18216.

It is an arithmetic number, because the mean of its divisors is an integer number (22839216).

Almost surely, 2^91323431 is an apocalyptic number.

91323431 is a deficient number, since it is larger than the sum of its proper divisors (33433).

91323431 is a wasteful number, since it uses less digits than its factorization.

91323431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33432.

The product of its digits is 1944, while the sum is 26.

The square root of 91323431 is about 9556.3293685389. The cubic root of 91323431 is about 450.3263985870.

The spelling of 91323431 in words is "ninety-one million, three hundred twenty-three thousand, four hundred thirty-one".