21443552240 has 120 divisors (see below), whose sum is σ = 55198394160. Its totient is φ = 7741071360.

The previous prime is 21443552231. The next prime is 21443552261. The reversal of 21443552240 is 4225534412.

It is a junction number, because it is equal to n+sod(n) for n = 21443552197 and 21443552206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1337552 + ... + 1353488.

It is an arithmetic number, because the mean of its divisors is an integer number (459986618).

Almost surely, 2^21443552240 is an apocalyptic number.

21443552240 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 21443552240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27599197080).

21443552240 is an abundant number, since it is smaller than the sum of its proper divisors (33754841920).

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

21443552240 is a wasteful number, since it uses less digits than its factorization.

21443552240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16111 (or 16094 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 32.

The spelling of 21443552240 in words is "twenty-one billion, four hundred forty-three million, five hundred fifty-two thousand, two hundred forty".