91938393 has 6 divisors (see below), whose sum is σ = 132799914. Its totient is φ = 61292256.

The previous prime is 91938389. The next prime is 91938421. The reversal of 91938393 is 39383919.

It can be written as a sum of positive squares in only one way, i.e., 91929744 + 8649 = 9588^2 + 93^2 .

It is not a de Polignac number, because 91938393 - 2² = 91938389 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91938893) 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 5 ways as a sum of consecutive naturals, for example, 5107680 + ... + 5107697.

It is an arithmetic number, because the mean of its divisors is an integer number (22133319).

Almost surely, 2^91938393 is an apocalyptic number.

It is an amenable number.

91938393 is a deficient number, since it is larger than the sum of its proper divisors (40861521).

91938393 is a wasteful number, since it uses less digits than its factorization.

91938393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10215383 (or 10215380 counting only the distinct ones).

The product of its digits is 157464, while the sum is 45.

The square root of 91938393 is about 9588.4510219326. The cubic root of 91938393 is about 451.3349543731.

The spelling of 91938393 in words is "ninety-one million, nine hundred thirty-eight thousand, three hundred ninety-three".