19908684949 has 2 divisors, whose sum is σ = 19908684950. Its totient is φ = 19908684948.

The previous prime is 19908684881. The next prime is 19908684953. The reversal of 19908684949 is 94948680991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10425431025 + 9483253924 = 102105^2 + 97382^2 .

It is a cyclic number.

It is not a de Polignac number, because 19908684949 - 2¹¹ = 19908682901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19908684749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9954342474 + 9954342475.

It is an arithmetic number, because the mean of its divisors is an integer number (9954342475).

Almost surely, 2^19908684949 is an apocalyptic number.

It is an amenable number.

19908684949 is a deficient number, since it is larger than the sum of its proper divisors (1).

19908684949 is an equidigital number, since it uses as much as digits as its factorization.

19908684949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40310784, while the sum is 67.

The spelling of 19908684949 in words is "nineteen billion, nine hundred eight million, six hundred eighty-four thousand, nine hundred forty-nine".