18401257 has 8 divisors (see below), whose sum is σ = 21067200. Its totient is φ = 15744624.

The previous prime is 18401221. The next prime is 18401261. The reversal of 18401257 is 75210481.

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

It is not a de Polignac number, because 18401257 - 2⁷ = 18401129 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18401287) 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 7 ways as a sum of consecutive naturals, for example, 2619 + ... + 6607.

It is an arithmetic number, because the mean of its divisors is an integer number (2633400).

Almost surely, 2^18401257 is an apocalyptic number.

It is an amenable number.

18401257 is a deficient number, since it is larger than the sum of its proper divisors (2665943).

18401257 is an equidigital number, since it uses as much as digits as its factorization.

18401257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4655.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 18401257 is about 4289.6686352211. The cubic root of 18401257 is about 264.0072359893.

The spelling of 18401257 in words is "eighteen million, four hundred one thousand, two hundred fifty-seven".