19906739 has 2 divisors, whose sum is σ = 19906740. Its totient is φ = 19906738.

The previous prime is 19906727. The next prime is 19906751. The reversal of 19906739 is 93760991.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (19906727) and next prime (19906751).

It is a cyclic number.

It is not a de Polignac number, because 19906739 - 2⁴ = 19906723 is a prime.

It is a super-2 number, since 2×19906739² = 792556515228242, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19906739.

It is not a weakly prime, because it can be changed into another prime (19906759) 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, 9953369 + 9953370.

It is an arithmetic number, because the mean of its divisors is an integer number (9953370).

Almost surely, 2^19906739 is an apocalyptic number.

19906739 is a deficient number, since it is larger than the sum of its proper divisors (1).

19906739 is an equidigital number, since it uses as much as digits as its factorization.

19906739 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91854, while the sum is 44.

The square root of 19906739 is about 4461.6968745086. The cubic root of 19906739 is about 271.0191886487.

The spelling of 19906739 in words is "nineteen million, nine hundred six thousand, seven hundred thirty-nine".