91796021 has 4 divisors (see below), whose sum is σ = 92109612. Its totient is φ = 91482432.

The previous prime is 91796009. The next prime is 91796027. The reversal of 91796021 is 12069719.

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 45024100 + 46771921 = 6710^2 + 6839^2 .

It is a cyclic number.

It is not a de Polignac number, because 91796021 - 2¹⁸ = 91533877 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 (91796027) 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, 156356 + ... + 156941.

It is an arithmetic number, because the mean of its divisors is an integer number (23027403).

Almost surely, 2^91796021 is an apocalyptic number.

It is an amenable number.

91796021 is a deficient number, since it is larger than the sum of its proper divisors (313591).

91796021 is a wasteful number, since it uses less digits than its factorization.

91796021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313590.

The product of its (nonzero) digits is 6804, while the sum is 35.

The square root of 91796021 is about 9581.0240058148. The cubic root of 91796021 is about 451.1018611194.

The spelling of 91796021 in words is "ninety-one million, seven hundred ninety-six thousand, twenty-one".