19945368720 has 200 divisors, whose sum is σ = 69580899960. Its totient is φ = 5295144960.

The previous prime is 19945368697. The next prime is 19945368743. The reversal of 19945368720 is 2786354991.

19945368720 is a `hidden beast` number, since 1 + 9 + 9 + 4 + 536 + 87 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (19945368697) and next prime (19945368743).

It can be written as a sum of positive squares in 4 ways, for example, as 2736126864 + 17209241856 = 52308^2 + 131184^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1477200 + ... + 1490640.

It is a 1-persistent number, because it is pandigital, but 2⋅19945368720 = 39890737440 is not.

Almost surely, 2^19945368720 is an apocalyptic number.

19945368720 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 19945368720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34790449980).

19945368720 is an abundant number, since it is smaller than the sum of its proper divisors (49635531240).

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

19945368720 is a wasteful number, since it uses less digits than its factorization.

19945368720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13695 (or 13680 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 54.

The spelling of 19945368720 in words is "nineteen billion, nine hundred forty-five million, three hundred sixty-eight thousand, seven hundred twenty".