91990523 has 8 divisors (see below), whose sum is σ = 96369600. Its totient is φ = 87691968.

The previous prime is 91990487. The next prime is 91990541. The reversal of 91990523 is 32509919.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91990523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91990543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17786 + ... + 22367.

It is an arithmetic number, because the mean of its divisors is an integer number (12046200).

Almost surely, 2^91990523 is an apocalyptic number.

91990523 is a deficient number, since it is larger than the sum of its proper divisors (4379077).

91990523 is a wasteful number, since it uses less digits than its factorization.

91990523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40261.

The product of its (nonzero) digits is 21870, while the sum is 38.

The square root of 91990523 is about 9591.1690111269. The cubic root of 91990523 is about 451.4202420856.

The spelling of 91990523 in words is "ninety-one million, nine hundred ninety thousand, five hundred twenty-three".