2121310440 has 48 divisors (see below), whose sum is σ = 6894260100. Its totient is φ = 565682688.

The previous prime is 2121310421. The next prime is 2121310453. The reversal of 2121310440 is 440131212.

2121310440 is a `hidden beast` number, since 2 + 1 + 213 + 10 + 440 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2083192164 + 38118276 = 45642^2 + 6174^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2945905 + ... + 2946624.

Almost surely, 2^2121310440 is an apocalyptic number.

2121310440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121310440 is an abundant number, since it is smaller than the sum of its proper divisors (4772949660).

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

2121310440 is a wasteful number, since it uses less digits than its factorization.

2121310440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5892546 (or 5892539 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 2121310440 is about 46057.6860035326. The cubic root of 2121310440 is about 1284.8962938709.

Adding to 2121310440 its reverse (440131212), we get a palindrome (2561441652).

The spelling of 2121310440 in words is "two billion, one hundred twenty-one million, three hundred ten thousand, four hundred forty".