2181522340 has 12 divisors (see below), whose sum is σ = 4581196956. Its totient is φ = 872608928.

The previous prime is 2181522323. The next prime is 2181522341. The reversal of 2181522340 is 432251812.

It can be written as a sum of positive squares in 2 ways, for example, as 357890724 + 1823631616 = 18918^2 + 42704^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2181522299 and 2181522308.

It is not an unprimeable number, because it can be changed into a prime (2181522341) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54538039 + ... + 54538078.

It is an arithmetic number, because the mean of its divisors is an integer number (381766413).

Almost surely, 2^2181522340 is an apocalyptic number.

2181522340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2181522340 is an abundant number, since it is smaller than the sum of its proper divisors (2399674616).

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

2181522340 is a wasteful number, since it uses less digits than its factorization.

2181522340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109076126 (or 109076124 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 2181522340 is about 46706.7697448667. The cubic root of 2181522340 is about 1296.9400100299.

The spelling of 2181522340 in words is "two billion, one hundred eighty-one million, five hundred twenty-two thousand, three hundred forty".