91145819 has 4 divisors (see below), whose sum is σ = 91197960. Its totient is φ = 91093680.

The previous prime is 91145801. The next prime is 91145827. The reversal of 91145819 is 91854119.

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 91145819 - 2¹² = 91141723 is a prime.

It is a super-2 number, since 2×91145819² = 16615120642361522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91135819) 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, 23354 + ... + 26975.

It is an arithmetic number, because the mean of its divisors is an integer number (22799490).

Almost surely, 2^91145819 is an apocalyptic number.

91145819 is a deficient number, since it is larger than the sum of its proper divisors (52141).

91145819 is a wasteful number, since it uses less digits than its factorization.

91145819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52140.

The product of its digits is 12960, while the sum is 38.

The square root of 91145819 is about 9547.0319471551. The cubic root of 91145819 is about 450.0342673493.

The spelling of 91145819 in words is "ninety-one million, one hundred forty-five thousand, eight hundred nineteen".