2181321510 has 128 divisors (see below), whose sum is σ = 5753991168. Its totient is φ = 526848000.

The previous prime is 2181321503. The next prime is 2181321511. The reversal of 2181321510 is 151231812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181321511) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4442365 + ... + 4442855.

It is an arithmetic number, because the mean of its divisors is an integer number (44953056).

Almost surely, 2^2181321510 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2181321510, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2876995584).

2181321510 is an abundant number, since it is smaller than the sum of its proper divisors (3572669658).

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

2181321510 is a wasteful number, since it uses less digits than its factorization.

2181321510 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 830.

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 2181321510 is about 46704.6197929070. The cubic root of 2181321510 is about 1296.9002102304.

The spelling of 2181321510 in words is "two billion, one hundred eighty-one million, three hundred twenty-one thousand, five hundred ten".