91673712931 has 4 divisors (see below), whose sum is σ = 91823262832. Its totient is φ = 91524163032.

The previous prime is 91673712917. The next prime is 91673712973. The reversal of 91673712931 is 13921737619.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13921737619 = 77243 ⋅180233.

It is a cyclic number.

It is not a de Polignac number, because 91673712931 - 2¹¹ = 91673710883 is a prime.

It is a super-2 number, since 2×91673712931² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91673712631) 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, 74774031 + ... + 74775256.

It is an arithmetic number, because the mean of its divisors is an integer number (22955815708).

Almost surely, 2^91673712931 is an apocalyptic number.

91673712931 is a deficient number, since it is larger than the sum of its proper divisors (149549901).

91673712931 is a wasteful number, since it uses less digits than its factorization.

91673712931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149549900.

The product of its digits is 428652, while the sum is 49.

The spelling of 91673712931 in words is "ninety-one billion, six hundred seventy-three million, seven hundred twelve thousand, nine hundred thirty-one".