91983993 has 8 divisors (see below), whose sum is σ = 123281568. Its totient is φ = 61004544.

The previous prime is 91983977. The next prime is 91984001. The reversal of 91983993 is 39938919.

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

It is not a de Polignac number, because 91983993 - 2⁴ = 91983977 is a prime.

It is a super-2 number, since 2×91983993² = 16922109936448098, which contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (91983943) 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, 78855 + ... + 80012.

It is an arithmetic number, because the mean of its divisors is an integer number (15410196).

Almost surely, 2^91983993 is an apocalyptic number.

It is an amenable number.

91983993 is a deficient number, since it is larger than the sum of its proper divisors (31297575).

91983993 is a wasteful number, since it uses less digits than its factorization.

91983993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159063.

The product of its digits is 472392, while the sum is 51.

The square root of 91983993 is about 9590.8285877707. The cubic root of 91983993 is about 451.4095603913.

The spelling of 91983993 in words is "ninety-one million, nine hundred eighty-three thousand, nine hundred ninety-three".