91709873 has 4 divisors (see below), whose sum is σ = 94668288. Its totient is φ = 88751460.

The previous prime is 91709869. The next prime is 91709909. The reversal of 91709873 is 37890719.

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, and also an emirpimes, since its reverse is a distinct semiprime: 37890719 = 1531 ⋅24749.

It is a cyclic number.

It is not a de Polignac number, because 91709873 - 2² = 91709869 is a prime.

It is a super-2 number, since 2×91709873² = 16821401611352258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91709843) 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, 1479161 + ... + 1479222.

It is an arithmetic number, because the mean of its divisors is an integer number (23667072).

Almost surely, 2^91709873 is an apocalyptic number.

It is an amenable number.

91709873 is a deficient number, since it is larger than the sum of its proper divisors (2958415).

91709873 is a wasteful number, since it uses less digits than its factorization.

91709873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2958414.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 91709873 is about 9576.5271889135. The cubic root of 91709873 is about 450.9607014559.

The spelling of 91709873 in words is "ninety-one million, seven hundred nine thousand, eight hundred seventy-three".