91440163 has 4 divisors (see below), whose sum is σ = 91527408. Its totient is φ = 91352920.

The previous prime is 91440143. The next prime is 91440169. The reversal of 91440163 is 36104419.

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

It is a cyclic number.

It is not a de Polignac number, because 91440163 - 2⁵ = 91440131 is a prime.

It is a super-2 number, since 2×91440163² = 16722606818933138, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91440169) 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, 42031 + ... + 44152.

It is an arithmetic number, because the mean of its divisors is an integer number (22881852).

Almost surely, 2^91440163 is an apocalyptic number.

91440163 is a deficient number, since it is larger than the sum of its proper divisors (87245).

91440163 is a wasteful number, since it uses less digits than its factorization.

91440163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87244.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 91440163 is about 9562.4349932431. The cubic root of 91440163 is about 450.5181898894.

The spelling of 91440163 in words is "ninety-one million, four hundred forty thousand, one hundred sixty-three".