2180645 has 8 divisors (see below), whose sum is σ = 2628504. Its totient is φ = 1736704.

The previous prime is 2180627. The next prime is 2180677. The reversal of 2180645 is 5460812.

It can be written as a sum of positive squares in 4 ways, for example, as 1437601 + 743044 = 1199^2 + 862^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2180645 - 2⁸ = 2180389 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 437 + ... + 2133.

It is an arithmetic number, because the mean of its divisors is an integer number (328563).

2^2180645 is an apocalyptic number.

It is an amenable number.

2180645 is a deficient number, since it is larger than the sum of its proper divisors (447859).

2180645 is a wasteful number, since it uses less digits than its factorization.

2180645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1959.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 2180645 is about 1476.7007144307. The cubic root of 2180645 is about 129.6766123825.

The spelling of 2180645 in words is "two million, one hundred eighty thousand, six hundred forty-five".