19477818671820 has 96 divisors (see below), whose sum is σ = 55113872760576. Its totient is φ = 5139296928000.

The previous prime is 19477818671791. The next prime is 19477818671873. The reversal of 19477818671820 is 2817681877491.

It is a super-2 number, since 2×19477818671820² (a number of 27 digits) contains 22 as substring.

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, 8228167 + ... + 10327553.

It is an arithmetic number, because the mean of its divisors is an integer number (574102841256).

Almost surely, 2^{19477818671820} is an apocalyptic number.

19477818671820 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 19477818671820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27556936380288).

19477818671820 is an abundant number, since it is smaller than the sum of its proper divisors (35636054088756).

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

19477818671820 is a wasteful number, since it uses less digits than its factorization.

19477818671820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2101031 (or 2101029 counting only the distinct ones).

The product of its (nonzero) digits is 75866112, while the sum is 69.

The spelling of 19477818671820 in words is "nineteen trillion, four hundred seventy-seven billion, eight hundred eighteen million, six hundred seventy-one thousand, eight hundred twenty".