21443132256 has 288 divisors, whose sum is σ = 71183962080. Its totient is φ = 5601705984.

The previous prime is 21443132251. The next prime is 21443132261. The reversal of 21443132256 is 65223134412.

It is an interprime number because it is at equal distance from previous prime (21443132251) and next prime (21443132261).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21443132251) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6663960 + ... + 6667176.

It is an arithmetic number, because the mean of its divisors is an integer number (247166535).

Almost surely, 2^21443132256 is an apocalyptic number.

21443132256 is a gapful number since it is divisible by the number (26) 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 21443132256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35591981040).

21443132256 is an abundant number, since it is smaller than the sum of its proper divisors (49740829824).

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

21443132256 is a wasteful number, since it uses less digits than its factorization.

21443132256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3366 (or 3351 counting only the distinct ones).

The product of its digits is 34560, while the sum is 33.

Adding to 21443132256 its reverse (65223134412), we get a palindrome (86666266668).

The spelling of 21443132256 in words is "twenty-one billion, four hundred forty-three million, one hundred thirty-two thousand, two hundred fifty-six".