19819236994 has 4 divisors (see below), whose sum is σ = 29728855494. Its totient is φ = 9909618496.

The previous prime is 19819236991. The next prime is 19819237001. The reversal of 19819236994 is 49963291891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49963291891 = 661 ⋅75587431.

It can be written as a sum of positive squares in only one way, i.e., 19372464225 + 446772769 = 139185^2 + 21137^2 .

It is not an unprimeable number, because it can be changed into a prime (19819236991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4954809247 + ... + 4954809250.

Almost surely, 2^19819236994 is an apocalyptic number.

19819236994 is a deficient number, since it is larger than the sum of its proper divisors (9909618500).

19819236994 is an equidigital number, since it uses as much as digits as its factorization.

19819236994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9909618499.

The product of its digits is 7558272, while the sum is 61.

The spelling of 19819236994 in words is "nineteen billion, eight hundred nineteen million, two hundred thirty-six thousand, nine hundred ninety-four".