21113434240 has 64 divisors (see below), whose sum is σ = 53443407960. Its totient is φ = 7948582912.

The previous prime is 21113434217. The next prime is 21113434241. The reversal of 21113434240 is 4243431112.

It can be written as a sum of positive squares in 4 ways, for example, as 19539566656 + 1573867584 = 139784^2 + 39672^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (21113434241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 959407 + ... + 981166.

Almost surely, 2^21113434240 is an apocalyptic number.

21113434240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21113434240 is an abundant number, since it is smaller than the sum of its proper divisors (32329973720).

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

21113434240 is a wasteful number, since it uses less digits than its factorization.

21113434240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1940609 (or 1940597 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 21113434240 its reverse (4243431112), we get a palindrome (25356865352).

The spelling of 21113434240 in words is "twenty-one billion, one hundred thirteen million, four hundred thirty-four thousand, two hundred forty".