20608139 has 2 divisors, whose sum is σ = 20608140. Its totient is φ = 20608138.

The previous prime is 20608129. The next prime is 20608187. The reversal of 20608139 is 93180602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20608139 - 2¹⁶ = 20542603 is a prime.

It is not a weakly prime, because it can be changed into another prime (20608129) 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, 10304069 + 10304070.

It is an arithmetic number, because the mean of its divisors is an integer number (10304070).

Almost surely, 2^20608139 is an apocalyptic number.

20608139 is a deficient number, since it is larger than the sum of its proper divisors (1).

20608139 is an equidigital number, since it uses as much as digits as its factorization.

20608139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 20608139 is about 4539.6188165968. The cubic root of 20608139 is about 274.1655764819.

The spelling of 20608139 in words is "twenty million, six hundred eight thousand, one hundred thirty-nine".