91206997 has 4 divisors (see below), whose sum is σ = 104236576. Its totient is φ = 78177420.

The previous prime is 91206953. The next prime is 91207007. The reversal of 91206997 is 79960219.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79960219 = 37 ⋅2161087.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91206997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91206917) 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, 6514779 + ... + 6514792.

It is an arithmetic number, because the mean of its divisors is an integer number (26059144).

Almost surely, 2^91206997 is an apocalyptic number.

It is an amenable number.

91206997 is a deficient number, since it is larger than the sum of its proper divisors (13029579).

91206997 is a wasteful number, since it uses less digits than its factorization.

91206997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13029578.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 91206997 is about 9550.2354421239. The cubic root of 91206997 is about 450.1349340211.

The spelling of 91206997 in words is "ninety-one million, two hundred six thousand, nine hundred ninety-seven".