19639704450 has 24 divisors (see below), whose sum is σ = 48706467408. Its totient is φ = 5237254480.

The previous prime is 19639704449. The next prime is 19639704499. The reversal of 19639704450 is 5440793691.

It is a self number, because there is not a number n which added to its sum of digits gives 19639704450.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65465532 + ... + 65465831.

It is an arithmetic number, because the mean of its divisors is an integer number (2029436142).

Almost surely, 2^19639704450 is an apocalyptic number.

19639704450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19639704450 is an abundant number, since it is smaller than the sum of its proper divisors (29066762958).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19639704450 is a wasteful number, since it uses less digits than its factorization.

19639704450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130931378 (or 130931373 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 48.

The spelling of 19639704450 in words is "nineteen billion, six hundred thirty-nine million, seven hundred four thousand, four hundred fifty".