91224017216993 has 4 divisors (see below), whose sum is σ = 92031309404868. Its totient is φ = 90416725029120.

The previous prime is 91224017216963. The next prime is 91224017216999. The reversal of 91224017216993 is 39961271042219.

It is a happy number.

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 38423782510864 + 52800234706129 = 6198692^2 + 7266377^2 .

It is a cyclic number.

It is not a de Polignac number, because 91224017216993 - 2²⁶ = 91223950108129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91224017216999) 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, 403646093768 + ... + 403646093993.

It is an arithmetic number, because the mean of its divisors is an integer number (23007827351217).

Almost surely, 2^{91224017216993} is an apocalyptic number.

It is an amenable number.

91224017216993 is a deficient number, since it is larger than the sum of its proper divisors (807292187875).

91224017216993 is a wasteful number, since it uses less digits than its factorization.

91224017216993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 807292187874.

The product of its (nonzero) digits is 2939328, while the sum is 56.

The spelling of 91224017216993 in words is "ninety-one trillion, two hundred twenty-four billion, seventeen million, two hundred sixteen thousand, nine hundred ninety-three".