18897679 has 4 divisors (see below), whose sum is σ = 19358640. Its totient is φ = 18436720.

The previous prime is 18897677. The next prime is 18897691. The reversal of 18897679 is 97679881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97679881 = 13 ⋅7513837.

It is a cyclic number.

It is not a de Polignac number, because 18897679 - 2¹ = 18897677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18897673) 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 3 ways as a sum of consecutive naturals, for example, 230419 + ... + 230500.

It is an arithmetic number, because the mean of its divisors is an integer number (4839660).

Almost surely, 2^18897679 is an apocalyptic number.

18897679 is a deficient number, since it is larger than the sum of its proper divisors (460961).

18897679 is an equidigital number, since it uses as much as digits as its factorization.

18897679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460960.

The product of its digits is 1524096, while the sum is 55.

The square root of 18897679 is about 4347.1460753004. The cubic root of 18897679 is about 266.3602962394.

The spelling of 18897679 in words is "eighteen million, eight hundred ninety-seven thousand, six hundred seventy-nine".