18839979 has 16 divisors (see below), whose sum is σ = 28051840. Its totient is φ = 12496680.

The previous prime is 18839969. The next prime is 18839981. The reversal of 18839979 is 97993881.

18839979 is a `hidden beast` number, since 188 + 399 + 79 = 666.

It is not a de Polignac number, because 18839979 - 2¹⁹ = 18315691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18839969) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4044 + ... + 7350.

It is an arithmetic number, because the mean of its divisors is an integer number (1753240).

Almost surely, 2^18839979 is an apocalyptic number.

18839979 is a deficient number, since it is larger than the sum of its proper divisors (9211861).

18839979 is a wasteful number, since it uses less digits than its factorization.

18839979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3527 (or 3521 counting only the distinct ones).

The product of its digits is 979776, while the sum is 54.

The square root of 18839979 is about 4340.5044637692. The cubic root of 18839979 is about 266.0889285643.

The spelling of 18839979 in words is "eighteen million, eight hundred thirty-nine thousand, nine hundred seventy-nine".