19949849 has 2 divisors, whose sum is σ = 19949850. Its totient is φ = 19949848.

The previous prime is 19949837. The next prime is 19949851. The reversal of 19949849 is 94894991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19536400 + 413449 = 4420^2 + 643^2 .

It is an emirp because it is prime and its reverse (94894991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19949849 is a prime.

Together with 19949851, it forms a pair of twin primes.

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 19949849.

It is not a weakly prime, because it can be changed into another prime (19949819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9974924 + 9974925.

It is an arithmetic number, because the mean of its divisors is an integer number (9974925).

Almost surely, 2^19949849 is an apocalyptic number.

It is an amenable number.

19949849 is a deficient number, since it is larger than the sum of its proper divisors (1).

19949849 is an equidigital number, since it uses as much as digits as its factorization.

19949849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 53.

The square root of 19949849 is about 4466.5253833377. The cubic root of 19949849 is about 271.2146871569.

The spelling of 19949849 in words is "nineteen million, nine hundred forty-nine thousand, eight hundred forty-nine".