2178172368 has 120 divisors (see below), whose sum is σ = 6330324000. Its totient is φ = 698326272.

The previous prime is 2178172361. The next prime is 2178172391. The reversal of 2178172368 is 8632718712.

2178172368 is a `hidden beast` number, since 217 + 8 + 1 + 72 + 368 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2178172361) 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, 1281183 + ... + 1282881.

It is an arithmetic number, because the mean of its divisors is an integer number (52752700).

Almost surely, 2^2178172368 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 2178172368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3165162000).

2178172368 is an abundant number, since it is smaller than the sum of its proper divisors (4152151632).

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

2178172368 is a wasteful number, since it uses less digits than its factorization.

2178172368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2049 (or 2040 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 2178172368 is about 46670.8942275590. The cubic root of 2178172368 is about 1296.2758043558.

It can be divided in two parts, 21781 and 72368, that added together give a palindrome (94149).

The spelling of 2178172368 in words is "two billion, one hundred seventy-eight million, one hundred seventy-two thousand, three hundred sixty-eight".