18488857 has 2 divisors, whose sum is σ = 18488858. Its totient is φ = 18488856.

The previous prime is 18488819. The next prime is 18488867. The reversal of 18488857 is 75888481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18412681 + 76176 = 4291^2 + 276^2 .

It is an emirp because it is prime and its reverse (75888481) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18488857 - 2²³ = 10100249 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18488857.

It is not a weakly prime, because it can be changed into another prime (18488867) 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 as a sum of consecutive naturals, namely, 9244428 + 9244429.

It is an arithmetic number, because the mean of its divisors is an integer number (9244429).

Almost surely, 2^18488857 is an apocalyptic number.

It is an amenable number.

18488857 is a deficient number, since it is larger than the sum of its proper divisors (1).

18488857 is an equidigital number, since it uses as much as digits as its factorization.

18488857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 573440, while the sum is 49.

The square root of 18488857 is about 4299.8670909692. The cubic root of 18488857 is about 264.4255123338.

The spelling of 18488857 in words is "eighteen million, four hundred eighty-eight thousand, eight hundred fifty-seven".