91079618437 has 4 divisors (see below), whose sum is σ = 91090721740. Its totient is φ = 91068515136.

The previous prime is 91079618419. The next prime is 91079618447. The reversal of 91079618437 is 73481697019.

It is a Cunningham number, because it is equal to 301794²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73481697019 = 1097 ⋅66984227.

It can be written as a sum of positive squares in 2 ways, for example, as 6300231876 + 84779386561 = 79374^2 + 291169^2 .

It is a cyclic number.

It is not a de Polignac number, because 91079618437 - 2⁷ = 91079618309 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 (91079618447) 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, 5539338 + ... + 5555755.

It is an arithmetic number, because the mean of its divisors is an integer number (22772680435).

Almost surely, 2^91079618437 is an apocalyptic number.

It is an amenable number.

91079618437 is a deficient number, since it is larger than the sum of its proper divisors (11103303).

91079618437 is a wasteful number, since it uses less digits than its factorization.

91079618437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11103302.

The product of its (nonzero) digits is 2286144, while the sum is 55.

The spelling of 91079618437 in words is "ninety-one billion, seventy-nine million, six hundred eighteen thousand, four hundred thirty-seven".