91947 has 4 divisors (see below), whose sum is σ = 122600. Its totient is φ = 61296.

The previous prime is 91943. The next prime is 91951. The reversal of 91947 is 74919.

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

It is an interprime number because it is at equal distance from previous prime (91943) and next prime (91951).

It is not a de Polignac number, because 91947 - 2² = 91943 is a prime.

It is a D-number.

It is a Duffinian number.

91947 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 91947.

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, 15322 + ... + 15327.

It is an arithmetic number, because the mean of its divisors is an integer number (30650).

2⁹¹⁹⁴⁷ is an apocalyptic number.

91947 is a deficient number, since it is larger than the sum of its proper divisors (30653).

91947 is a wasteful number, since it uses less digits than its factorization.

91947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30652.

The product of its digits is 2268, while the sum is 30.

The square root of 91947 is about 303.2276372628. The cubic root of 91947 is about 45.1349038147.

The spelling of 91947 in words is "ninety-one thousand, nine hundred forty-seven".