19771668609888 has 144 divisors (see below), whose sum is σ = 56209262271120. Its totient is φ = 6082597527552.

The previous prime is 19771668609871. The next prime is 19771668609899. The reversal of 19771668609888 is 88890686617791.

It is a self number, because there is not a number n which added to its sum of digits gives 19771668609888.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 102585420 + ... + 102777972.

It is an arithmetic number, because the mean of its divisors is an integer number (390342099105).

Almost surely, 2^{19771668609888} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19771668609888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28104631135560).

19771668609888 is an abundant number, since it is smaller than the sum of its proper divisors (36437593661232).

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

19771668609888 is a wasteful number, since it uses less digits than its factorization.

19771668609888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198921 (or 198900 counting only the distinct ones).

The product of its (nonzero) digits is 3511517184, while the sum is 84.

The spelling of 19771668609888 in words is "nineteen trillion, seven hundred seventy-one billion, six hundred sixty-eight million, six hundred nine thousand, eight hundred eighty-eight".