18871918128 has 120 divisors (see below), whose sum is σ = 60403419648. Its totient is φ = 5388114816.

The previous prime is 18871918123. The next prime is 18871918139. The reversal of 18871918128 is 82181917881.

It is a super-2 number, since 2×18871918128² (a number of 21 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (18871918123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1589751 + ... + 1601577.

Almost surely, 2^18871918128 is an apocalyptic number.

18871918128 is a gapful number since it is divisible by the number (18) 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 18871918128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30201709824).

18871918128 is an abundant number, since it is smaller than the sum of its proper divisors (41531501520).

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

18871918128 is a wasteful number, since it uses less digits than its factorization.

18871918128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13431 (or 13422 counting only the distinct ones).

The product of its digits is 516096, while the sum is 54.

The spelling of 18871918128 in words is "eighteen billion, eight hundred seventy-one million, nine hundred eighteen thousand, one hundred twenty-eight".