91913 has 4 divisors (see below), whose sum is σ = 92880. Its totient is φ = 90948.

The previous prime is 91909. The next prime is 91921. The reversal of 91913 is 31919.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 31919 = 59 ⋅541.

It is a cyclic number.

It is not a de Polignac number, because 91913 - 2² = 91909 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91943) 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, 323 + ... + 536.

It is an arithmetic number, because the mean of its divisors is an integer number (23220).

2⁹¹⁹¹³ is an apocalyptic number.

It is an amenable number.

91913 is a deficient number, since it is larger than the sum of its proper divisors (967).

91913 is a wasteful number, since it uses less digits than its factorization.

91913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 966.

The product of its digits is 243, while the sum is 23.

The square root of 91913 is about 303.1715685878. The cubic root of 91913 is about 45.1293398271.

The spelling of 91913 in words is "ninety-one thousand, nine hundred thirteen".