18440857 has 8 divisors (see below), whose sum is σ = 19121760. Its totient is φ = 17771040.

The previous prime is 18440833. The next prime is 18440861. The reversal of 18440857 is 75804481.

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

It is not a de Polignac number, because 18440857 - 2²³ = 10052249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18440867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 694 + ... + 6112.

It is an arithmetic number, because the mean of its divisors is an integer number (2390220).

Almost surely, 2^18440857 is an apocalyptic number.

It is an amenable number.

18440857 is a deficient number, since it is larger than the sum of its proper divisors (680903).

18440857 is an equidigital number, since it uses as much as digits as its factorization.

18440857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5543.

The product of its (nonzero) digits is 35840, while the sum is 37.

The square root of 18440857 is about 4294.2818957306. The cubic root of 18440857 is about 264.1964838563.

It can be divided in two parts, 184 and 40857, that added together give a triangular number (41041 = T₂₈₆).

The spelling of 18440857 in words is "eighteen million, four hundred forty thousand, eight hundred fifty-seven".