19719697920 has 320 divisors, whose sum is σ = 68239632384. Its totient is φ = 4829184000.

The previous prime is 19719697819. The next prime is 19719697931. The reversal of 19719697920 is 2979691791.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26257545 + ... + 26258295.

Almost surely, 2^19719697920 is an apocalyptic number.

19719697920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19719697920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34119816192).

19719697920 is an abundant number, since it is smaller than the sum of its proper divisors (48519934464).

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

19719697920 is a wasteful number, since it uses less digits than its factorization.

19719697920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053 (or 1037 counting only the distinct ones).

The product of its (nonzero) digits is 3857868, while the sum is 60.

The spelling of 19719697920 in words is "nineteen billion, seven hundred nineteen million, six hundred ninety-seven thousand, nine hundred twenty".