21433254440 has 128 divisors (see below), whose sum is σ = 53240181120. Its totient is φ = 7717248000.

The previous prime is 21433254419. The next prime is 21433254449. The reversal of 21433254440 is 4445233412.

It is a junction number, because it is equal to n+sod(n) for n = 21433254397 and 21433254406.

It is not an unprimeable number, because it can be changed into a prime (21433254449) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3515795 + ... + 3521885.

It is an arithmetic number, because the mean of its divisors is an integer number (415938915).

Almost surely, 2^21433254440 is an apocalyptic number.

21433254440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21433254440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26620090560).

21433254440 is an abundant number, since it is smaller than the sum of its proper divisors (31806926680).

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

21433254440 is a wasteful number, since it uses less digits than its factorization.

21433254440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6283 (or 6279 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 32.

Adding to 21433254440 its reverse (4445233412), we get a palindrome (25878487852).

The spelling of 21433254440 in words is "twenty-one billion, four hundred thirty-three million, two hundred fifty-four thousand, four hundred forty".