18519857 has 4 divisors (see below), whose sum is σ = 18531840. Its totient is φ = 18507876.

The previous prime is 18519847. The next prime is 18519859. The reversal of 18519857 is 75891581.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 75891581 = 2063 ⋅36787.

It is a cyclic number.

It is not a de Polignac number, because 18519857 - 2⁴ = 18519841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18519859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3257 + ... + 6902.

It is an arithmetic number, because the mean of its divisors is an integer number (4632960).

Almost surely, 2^18519857 is an apocalyptic number.

It is an amenable number.

18519857 is a deficient number, since it is larger than the sum of its proper divisors (11983).

18519857 is a wasteful number, since it uses less digits than its factorization.

18519857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11982.

The product of its digits is 100800, while the sum is 44.

The square root of 18519857 is about 4303.4703438039. The cubic root of 18519857 is about 264.5732159619.

The spelling of 18519857 in words is "eighteen million, five hundred nineteen thousand, eight hundred fifty-seven".