18572257 has 4 divisors (see below), whose sum is σ = 20260656. Its totient is φ = 16883860.

The previous prime is 18572249. The next prime is 18572287. The reversal of 18572257 is 75227581.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18572257 - 2³ = 18572249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18572227) 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 3 ways as a sum of consecutive naturals, for example, 844183 + ... + 844204.

It is an arithmetic number, because the mean of its divisors is an integer number (5065164).

Almost surely, 2^18572257 is an apocalyptic number.

It is an amenable number.

18572257 is a deficient number, since it is larger than the sum of its proper divisors (1688399).

18572257 is a wasteful number, since it uses less digits than its factorization.

18572257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1688398.

The product of its digits is 39200, while the sum is 37.

The square root of 18572257 is about 4309.5541532739. The cubic root of 18572257 is about 264.8225084158.

It can be divided in two parts, 1857 and 2257, that added together give a palindrome (4114).

The spelling of 18572257 in words is "eighteen million, five hundred seventy-two thousand, two hundred fifty-seven".