2180666 has 4 divisors (see below), whose sum is σ = 3271002. Its totient is φ = 1090332.

The previous prime is 2180627. The next prime is 2180677. The reversal of 2180666 is 6660812.

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

It can be written as a sum of positive squares in only one way, i.e., 2175625 + 5041 = 1475^2 + 71^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545165 + ... + 545168.

2^2180666 is an apocalyptic number.

2180666 is a deficient number, since it is larger than the sum of its proper divisors (1090336).

2180666 is a wasteful number, since it uses less digits than its factorization.

2180666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1090335.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 2180666 is about 1476.7078248591. The cubic root of 2180666 is about 129.6770286508.

The spelling of 2180666 in words is "two million, one hundred eighty thousand, six hundred sixty-six".