2180081 has 4 divisors (see below), whose sum is σ = 2196132. Its totient is φ = 2164032.

The previous prime is 2180071. The next prime is 2180083. The reversal of 2180081 is 1800812.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1540081 + 640000 = 1241^2 + 800^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2180081 is a prime.

It is a super-2 number, since 2×2180081² = 9505506333122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2180083) 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, 7820 + ... + 8093.

It is an arithmetic number, because the mean of its divisors is an integer number (549033).

2^2180081 is an apocalyptic number.

It is an amenable number.

2180081 is a deficient number, since it is larger than the sum of its proper divisors (16051).

2180081 is a wasteful number, since it uses less digits than its factorization.

2180081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16050.

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 2180081 is about 1476.5097358297. The cubic root of 2180081 is about 129.6654316056.

Adding to 2180081 its reverse (1800812), we get a palindrome (3980893).

The spelling of 2180081 in words is "two million, one hundred eighty thousand, eighty-one".