2181172170 has 16 divisors (see below), whose sum is σ = 5234813280. Its totient is φ = 581645904.

The previous prime is 2181172151. The next prime is 2181172211. The reversal of 2181172170 is 712711812.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 72705739 = 2181172170 / (2 + 1 + 8 + 1 + 1 + 7 + 2 + 1 + 7 + 0).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36352840 + ... + 36352899.

It is an arithmetic number, because the mean of its divisors is an integer number (327175830).

Almost surely, 2^2181172170 is an apocalyptic number.

2181172170 is an abundant number, since it is smaller than the sum of its proper divisors (3053641110).

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

2181172170 is a wasteful number, since it uses less digits than its factorization.

2181172170 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72705749.

The product of its (nonzero) digits is 1568, while the sum is 30.

The square root of 2181172170 is about 46703.0209943640. The cubic root of 2181172170 is about 1296.8706129585.

Adding to 2181172170 its reverse (712711812), we get a palindrome (2893883982).

The spelling of 2181172170 in words is "two billion, one hundred eighty-one million, one hundred seventy-two thousand, one hundred seventy".