2181285839 has 4 divisors (see below), whose sum is σ = 2227696224. Its totient is φ = 2134875456.

The previous prime is 2181285817. The next prime is 2181285871. The reversal of 2181285839 is 9385821812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2181285839 - 2⁸ = 2181285583 is a prime.

It is a super-2 number, since 2×2181285839² = 9516015822843867842, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47), and also a Moran number because the ratio is a prime number: 46410337 = 2181285839 / (2 + 1 + 8 + 1 + 2 + 8 + 5 + 8 + 3 + 9).

It is a junction number, because it is equal to n+sod(n) for n = 2181285793 and 2181285802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181285539) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23205122 + ... + 23205215.

It is an arithmetic number, because the mean of its divisors is an integer number (556924056).

Almost surely, 2^2181285839 is an apocalyptic number.

2181285839 is a deficient number, since it is larger than the sum of its proper divisors (46410385).

2181285839 is an equidigital number, since it uses as much as digits as its factorization.

2181285839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46410384.

The product of its digits is 276480, while the sum is 47.

The square root of 2181285839 is about 46704.2379126349. The cubic root of 2181285839 is about 1296.8931408187.

The spelling of 2181285839 in words is "two billion, one hundred eighty-one million, two hundred eighty-five thousand, eight hundred thirty-nine".