91381851 has 48 divisors (see below), whose sum is σ = 158191488. Its totient is φ = 52099200.

The previous prime is 91381793. The next prime is 91381859. The reversal of 91381851 is 15818319.

It is not a de Polignac number, because 91381851 - 2⁷ = 91381723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91381859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 44436 + ... + 46446.

It is an arithmetic number, because the mean of its divisors is an integer number (3295656).

Almost surely, 2^91381851 is an apocalyptic number.

91381851 is a deficient number, since it is larger than the sum of its proper divisors (66809637).

91381851 is a wasteful number, since it uses less digits than its factorization.

91381851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2054 (or 2042 counting only the distinct ones).

The product of its digits is 8640, while the sum is 36.

The square root of 91381851 is about 9559.3854928023. The cubic root of 91381851 is about 450.4224033768.

The spelling of 91381851 in words is "ninety-one million, three hundred eighty-one thousand, eight hundred fifty-one".