21243342040 has 32 divisors (see below), whose sum is σ = 48373400880. Its totient is φ = 8394957952.

The previous prime is 21243341983. The next prime is 21243342089. The reversal of 21243342040 is 4024334212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21243341996 and 21243342014.

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, 3195979 + ... + 3202618.

Almost surely, 2^21243342040 is an apocalyptic number.

21243342040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21243342040 is an abundant number, since it is smaller than the sum of its proper divisors (27130058840).

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

21243342040 is a wasteful number, since it uses less digits than its factorization.

21243342040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6398691 (or 6398687 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 25.

Adding to 21243342040 its reverse (4024334212), we get a palindrome (25267676252).

The spelling of 21243342040 in words is "twenty-one billion, two hundred forty-three million, three hundred forty-two thousand, forty".