19399739 has 2 divisors, whose sum is σ = 19399740. Its totient is φ = 19399738.

The previous prime is 19399717. The next prime is 19399747. The reversal of 19399739 is 93799391.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19399739 is a prime.

It is not a weakly prime, because it can be changed into another prime (19399789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9699869 + 9699870.

It is an arithmetic number, because the mean of its divisors is an integer number (9699870).

Almost surely, 2^19399739 is an apocalyptic number.

19399739 is a deficient number, since it is larger than the sum of its proper divisors (1).

19399739 is an equidigital number, since it uses as much as digits as its factorization.

19399739 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 413343, while the sum is 50.

The square root of 19399739 is about 4404.5134805106. The cubic root of 19399739 is about 268.6985332128.

The spelling of 19399739 in words is "nineteen million, three hundred ninety-nine thousand, seven hundred thirty-nine".