18939379 has 2 divisors, whose sum is σ = 18939380. Its totient is φ = 18939378.

The previous prime is 18939367. The next prime is 18939421. The reversal of 18939379 is 97393981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18939379 - 2¹⁹ = 18415091 is a prime.

It is not a weakly prime, because it can be changed into another prime (18939329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9469689 + 9469690.

It is an arithmetic number, because the mean of its divisors is an integer number (9469690).

Almost surely, 2^18939379 is an apocalyptic number.

18939379 is a deficient number, since it is larger than the sum of its proper divisors (1).

18939379 is an equidigital number, since it uses as much as digits as its factorization.

18939379 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 367416, while the sum is 49.

The square root of 18939379 is about 4351.9396824864. The cubic root of 18939379 is about 266.5560709788.

The spelling of 18939379 in words is "eighteen million, nine hundred thirty-nine thousand, three hundred seventy-nine".