19702139 has 2 divisors, whose sum is σ = 19702140. Its totient is φ = 19702138.

The previous prime is 19702129. The next prime is 19702141. The reversal of 19702139 is 93120791.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19702139 - 2²⁰ = 18653563 is a prime.

Together with 19702141, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19702129) 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, 9851069 + 9851070.

It is an arithmetic number, because the mean of its divisors is an integer number (9851070).

Almost surely, 2^19702139 is an apocalyptic number.

19702139 is a deficient number, since it is larger than the sum of its proper divisors (1).

19702139 is an equidigital number, since it uses as much as digits as its factorization.

19702139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 19702139 is about 4438.7091592038. The cubic root of 19702139 is about 270.0874842250.

The spelling of 19702139 in words is "nineteen million, seven hundred two thousand, one hundred thirty-nine".