18972671328 has 144 divisors (see below), whose sum is σ = 58172521680. Its totient is φ = 5830843392.

The previous prime is 18972671323. The next prime is 18972671423. The reversal of 18972671328 is 82317627981.

It is a happy number.

18972671328 is a `hidden beast` number, since 189 + 72 + 6 + 71 + 328 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18972671323) 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, 3812650 + ... + 3817622.

It is an arithmetic number, because the mean of its divisors is an integer number (403975845).

Almost surely, 2^18972671328 is an apocalyptic number.

18972671328 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 18972671328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29086260840).

18972671328 is an abundant number, since it is smaller than the sum of its proper divisors (39199850352).

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

18972671328 is a wasteful number, since it uses less digits than its factorization.

18972671328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6021 (or 6010 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

It can be divided in two parts, 1897 and 2671328, that added together give a square (2673225 = 1635²).

The spelling of 18972671328 in words is "eighteen billion, nine hundred seventy-two million, six hundred seventy-one thousand, three hundred twenty-eight".