21403244040 has 64 divisors (see below), whose sum is σ = 64412400960. Its totient is φ = 5689516800.

The previous prime is 21403244039. The next prime is 21403244053. The reversal of 21403244040 is 4044230412.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21403244040.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 243286 + ... + 319365.

It is an arithmetic number, because the mean of its divisors is an integer number (1006443765).

Almost surely, 2^21403244040 is an apocalyptic number.

21403244040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21403244040 is an abundant number, since it is smaller than the sum of its proper divisors (43009156920).

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

21403244040 is a wasteful number, since it uses less digits than its factorization.

21403244040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562982 (or 562978 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

Adding to 21403244040 its reverse (4044230412), we get a palindrome (25447474452).

The spelling of 21403244040 in words is "twenty-one billion, four hundred three million, two hundred forty-four thousand, forty".