2181237273 has 6 divisors (see below), whose sum is σ = 3150676074. Its totient is φ = 1454158176.

The previous prime is 2181237263. The next prime is 2181237277. The reversal of 2181237273 is 3727321812.

2181237273 is a `hidden beast` number, since 218 + 1 + 2 + 372 + 73 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1564360704 + 616876569 = 39552^2 + 24837^2 .

It is not a de Polignac number, because 2181237273 - 2⁸ = 2181237017 is a prime.

It is a super-2 number, since 2×2181237273² = 9515592082248953058, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2181237277) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 121179840 + ... + 121179857.

It is an arithmetic number, because the mean of its divisors is an integer number (525112679).

Almost surely, 2^2181237273 is an apocalyptic number.

It is an amenable number.

2181237273 is a deficient number, since it is larger than the sum of its proper divisors (969438801).

2181237273 is a wasteful number, since it uses less digits than its factorization.

2181237273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242359703 (or 242359700 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 2181237273 is about 46703.7179783366. The cubic root of 2181237273 is about 1296.8835157039.

The spelling of 2181237273 in words is "two billion, one hundred eighty-one million, two hundred thirty-seven thousand, two hundred seventy-three".