21412252240 has 40 divisors (see below), whose sum is σ = 51128993160. Its totient is φ = 8333415936.

The previous prime is 21412252223. The next prime is 21412252289. The reversal of 21412252240 is 4225221412.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 9546071616 + 11866180624 = 97704^2 + 108932^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3613975 + ... + 3619894.

It is an arithmetic number, because the mean of its divisors is an integer number (1278224829).

Almost surely, 2^21412252240 is an apocalyptic number.

21412252240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21412252240 is an abundant number, since it is smaller than the sum of its proper divisors (29716740920).

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

21412252240 is a wasteful number, since it uses less digits than its factorization.

21412252240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7233919 (or 7233913 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 25.

Adding to 21412252240 its reverse (4225221412), we get a palindrome (25637473652).

The spelling of 21412252240 in words is "twenty-one billion, four hundred twelve million, two hundred fifty-two thousand, two hundred forty".