18979487 has 2 divisors, whose sum is σ = 18979488. Its totient is φ = 18979486.

The previous prime is 18979453. The next prime is 18979511. The reversal of 18979487 is 78497981.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18979487 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18979087) 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 as a sum of consecutive naturals, namely, 9489743 + 9489744.

It is an arithmetic number, because the mean of its divisors is an integer number (9489744).

Almost surely, 2^18979487 is an apocalyptic number.

18979487 is a deficient number, since it is larger than the sum of its proper divisors (1).

18979487 is an equidigital number, since it uses as much as digits as its factorization.

18979487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1016064, while the sum is 53.

The square root of 18979487 is about 4356.5453056292. The cubic root of 18979487 is about 266.7441006030.

The spelling of 18979487 in words is "eighteen million, nine hundred seventy-nine thousand, four hundred eighty-seven".