19665255200 has 72 divisors (see below), whose sum is σ = 48048682500. Its totient is φ = 7859404800.

The previous prime is 19665255179. The next prime is 19665255209. The reversal of 19665255200 is 255256691.

It can be written as a sum of positive squares in 6 ways, for example, as 12568203664 + 7097051536 = 112108^2 + 84244^2 .

It is a super-2 number, since 2×19665255200² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19665255209) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 989360 + ... + 1009040.

Almost surely, 2^19665255200 is an apocalyptic number.

19665255200 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 19665255200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24024341250).

19665255200 is an abundant number, since it is smaller than the sum of its proper divisors (28383427300).

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

19665255200 is a wasteful number, since it uses less digits than its factorization.

19665255200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20950 (or 20937 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 41.

The spelling of 19665255200 in words is "nineteen billion, six hundred sixty-five million, two hundred fifty-five thousand, two hundred".