2181699648 has 168 divisors, whose sum is σ = 6564270336. Its totient is φ = 691891200.

The previous prime is 2181699647. The next prime is 2181699649. The reversal of 2181699648 is 8469961812.

It is an interprime number because it is at equal distance from previous prime (2181699647) and next prime (2181699649).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 2181699594 and 2181699603.

It is not an unprimeable number, because it can be changed into a prime (2181699647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1088215 + ... + 1090217.

Almost surely, 2^2181699648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2181699648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3282135168).

2181699648 is an abundant number, since it is smaller than the sum of its proper divisors (4382570688).

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

2181699648 is a wasteful number, since it uses less digits than its factorization.

2181699648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2113 (or 2100 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 54.

The square root of 2181699648 is about 46708.6678037385. The cubic root of 2181699648 is about 1296.9751462901.

The spelling of 2181699648 in words is "two billion, one hundred eighty-one million, six hundred ninety-nine thousand, six hundred forty-eight".