2180661668 has 12 divisors (see below), whose sum is σ = 3841431552. Its totient is φ = 1083109800.

The previous prime is 2180661667. The next prime is 2180661677. The reversal of 2180661668 is 8661660812.

It is not an unprimeable number, because it can be changed into a prime (2180661661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1804580 + ... + 1805787.

It is an arithmetic number, because the mean of its divisors is an integer number (320119296).

Almost surely, 2^2180661668 is an apocalyptic number.

It is an amenable number.

2180661668 is a deficient number, since it is larger than the sum of its proper divisors (1660769884).

2180661668 is a wasteful number, since it uses less digits than its factorization.

2180661668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3610522 (or 3610520 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 44.

The square root of 2180661668 is about 46697.5552679153. Note that the first 3 decimals coincide. The cubic root of 2180661668 is about 1296.7694278085.

The spelling of 2180661668 in words is "two billion, one hundred eighty million, six hundred sixty-one thousand, six hundred sixty-eight".