19966287616 has 72 divisors (see below), whose sum is σ = 43908823728. Its totient is φ = 8985600000.

The previous prime is 19966287613. The next prime is 19966287647. The reversal of 19966287616 is 61678266991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19966287611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 249316 + ... + 319516.

It is an arithmetic number, because the mean of its divisors is an integer number (609844774).

Almost surely, 2^19966287616 is an apocalyptic number.

19966287616 is a gapful number since it is divisible by the number (16) 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 19966287616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21954411864).

19966287616 is an abundant number, since it is smaller than the sum of its proper divisors (23942536112).

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

19966287616 is a wasteful number, since it uses less digits than its factorization.

19966287616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70329 (or 70315 counting only the distinct ones).

The product of its digits is 11757312, while the sum is 61.

The spelling of 19966287616 in words is "nineteen billion, nine hundred sixty-six million, two hundred eighty-seven thousand, six hundred sixteen".