19899409931 has 2 divisors, whose sum is σ = 19899409932. Its totient is φ = 19899409930.

The previous prime is 19899409889. The next prime is 19899409939. The reversal of 19899409931 is 13990499891.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (13990499891) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19899409931 is a prime.

It is a super-3 number, since 3×19899409931³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (19899409939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9949704965 + 9949704966.

It is an arithmetic number, because the mean of its divisors is an integer number (9949704966).

Almost surely, 2^19899409931 is an apocalyptic number.

19899409931 is a deficient number, since it is larger than the sum of its proper divisors (1).

19899409931 is an equidigital number, since it uses as much as digits as its factorization.

19899409931 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5668704, while the sum is 62.

The spelling of 19899409931 in words is "nineteen billion, eight hundred ninety-nine million, four hundred nine thousand, nine hundred thirty-one".