16581918672 has 160 divisors (see below), whose sum is σ = 52189695360. Its totient is φ = 4999034880.

The previous prime is 16581918653. The next prime is 16581918709. The reversal of 16581918672 is 27681918561.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 927288 + ... + 945000.

It is an arithmetic number, because the mean of its divisors is an integer number (326185596).

Almost surely, 2^16581918672 is an apocalyptic number.

16581918672 is a gapful number since it is divisible by the number (12) 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 16581918672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26094847680).

16581918672 is an abundant number, since it is smaller than the sum of its proper divisors (35607776688).

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

16581918672 is a wasteful number, since it uses less digits than its factorization.

16581918672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17938 (or 17926 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 54.

The spelling of 16581918672 in words is "sixteen billion, five hundred eighty-one million, nine hundred eighteen thousand, six hundred seventy-two".