19978299831 has 32 divisors (see below), whose sum is σ = 30809479680. Its totient is φ = 11278992384.

The previous prime is 19978299829. The next prime is 19978299833. The reversal of 19978299831 is 13899287991.

It is an interprime number because it is at equal distance from previous prime (19978299829) and next prime (19978299833).

It is not a de Polignac number, because 19978299831 - 2¹ = 19978299829 is a prime.

It is a super-2 number, since 2×19978299831² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (66) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19978299833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2899116 + ... + 2905998.

It is an arithmetic number, because the mean of its divisors is an integer number (962796240).

Almost surely, 2^19978299831 is an apocalyptic number.

19978299831 is a deficient number, since it is larger than the sum of its proper divisors (10831179849).

19978299831 is a wasteful number, since it uses less digits than its factorization.

19978299831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8535.

The product of its digits is 17635968, while the sum is 66.

The spelling of 19978299831 in words is "nineteen billion, nine hundred seventy-eight million, two hundred ninety-nine thousand, eight hundred thirty-one".