2181390768 has 60 divisors (see below), whose sum is σ = 6463981368. Its totient is φ = 684357120.

The previous prime is 2181390763. The next prime is 2181390769. The reversal of 2181390768 is 8670931812.

It is not an unprimeable number, because it can be changed into a prime (2181390763) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 443098 + ... + 447993.

Almost surely, 2^2181390768 is an apocalyptic number.

It is an amenable number.

2181390768 is an abundant number, since it is smaller than the sum of its proper divisors (4282590600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2181390768 is a wasteful number, since it uses less digits than its factorization.

2181390768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 891122 (or 891113 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 2181390768 is about 46705.3612340168. The cubic root of 2181390768 is about 1296.9139358189.

The spelling of 2181390768 in words is "two billion, one hundred eighty-one million, three hundred ninety thousand, seven hundred sixty-eight".