91172769 has 4 divisors (see below), whose sum is σ = 121563696. Its totient is φ = 60781844.

The previous prime is 91172749. The next prime is 91172797. The reversal of 91172769 is 96727119.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91172769 - 2⁵ = 91172737 is a prime.

It is a super-2 number, since 2×91172769² = 16624947614254722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91172769.

It is not an unprimeable number, because it can be changed into a prime (91172749) 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, 15195459 + ... + 15195464.

It is an arithmetic number, because the mean of its divisors is an integer number (30390924).

Almost surely, 2^91172769 is an apocalyptic number.

It is an amenable number.

91172769 is a deficient number, since it is larger than the sum of its proper divisors (30390927).

91172769 is a wasteful number, since it uses less digits than its factorization.

91172769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30390926.

The product of its digits is 47628, while the sum is 42.

The square root of 91172769 is about 9548.4432762624. The cubic root of 91172769 is about 450.0786183628.

The spelling of 91172769 in words is "ninety-one million, one hundred seventy-two thousand, seven hundred sixty-nine".