91687723 has 4 divisors (see below), whose sum is σ = 91789720. Its totient is φ = 91585728.

The previous prime is 91687679. The next prime is 91687733. The reversal of 91687723 is 32778619.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91687723 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91687723.

It is not an unprimeable number, because it can be changed into a prime (91687733) 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, 49638 + ... + 51451.

It is an arithmetic number, because the mean of its divisors is an integer number (22947430).

Almost surely, 2^91687723 is an apocalyptic number.

91687723 is a deficient number, since it is larger than the sum of its proper divisors (101997).

91687723 is a wasteful number, since it uses less digits than its factorization.

91687723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101996.

The product of its digits is 127008, while the sum is 43.

The square root of 91687723 is about 9575.3706455677. The cubic root of 91687723 is about 450.9243928104.

The spelling of 91687723 in words is "ninety-one million, six hundred eighty-seven thousand, seven hundred twenty-three".