18878579 has 2 divisors, whose sum is σ = 18878580. Its totient is φ = 18878578.

The previous prime is 18878569. The next prime is 18878581. The reversal of 18878579 is 97587881.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (97587881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18878579 - 2¹² = 18874483 is a prime.

Together with 18878581, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18878579.

It is not a weakly prime, because it can be changed into another prime (18878549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9439289 + 9439290.

It is an arithmetic number, because the mean of its divisors is an integer number (9439290).

Almost surely, 2^18878579 is an apocalyptic number.

18878579 is a deficient number, since it is larger than the sum of its proper divisors (1).

18878579 is an equidigital number, since it uses as much as digits as its factorization.

18878579 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1128960, while the sum is 53.

The square root of 18878579 is about 4344.9486763367. The cubic root of 18878579 is about 266.2705286617.

The spelling of 18878579 in words is "eighteen million, eight hundred seventy-eight thousand, five hundred seventy-nine".