91442993 has 4 divisors (see below), whose sum is σ = 91666980. Its totient is φ = 91219008.

The previous prime is 91442987. The next prime is 91443031. The reversal of 91442993 is 39924419.

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

It can be written as a sum of positive squares in 2 ways, for example, as 81126049 + 10316944 = 9007^2 + 3212^2 .

It is a cyclic number.

It is not a de Polignac number, because 91442993 - 2⁴ = 91442977 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 91442993.

It is not an unprimeable number, because it can be changed into a prime (91442903) 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, 111380 + ... + 112197.

It is an arithmetic number, because the mean of its divisors is an integer number (22916745).

Almost surely, 2^91442993 is an apocalyptic number.

It is an amenable number.

91442993 is a deficient number, since it is larger than the sum of its proper divisors (223987).

91442993 is a wasteful number, since it uses less digits than its factorization.

91442993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223986.

The product of its digits is 69984, while the sum is 41.

The square root of 91442993 is about 9562.5829669603. The cubic root of 91442993 is about 450.5228375675.

The spelling of 91442993 in words is "ninety-one million, four hundred forty-two thousand, nine hundred ninety-three".