21550324401440 has 48 divisors (see below), whose sum is σ = 50915504066112. Its totient is φ = 8619645076224.

The previous prime is 21550324401383. The next prime is 21550324401491. The reversal of 21550324401440 is 4410442305512.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21550324401440.

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, 925364 + ... + 6630003.

It is an arithmetic number, because the mean of its divisors is an integer number (1060739668044).

Almost surely, 2^{21550324401440} is an apocalyptic number.

21550324401440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21550324401440 is an abundant number, since it is smaller than the sum of its proper divisors (29365179664672).

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

21550324401440 is a wasteful number, since it uses less digits than its factorization.

21550324401440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7573209 (or 7573201 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 35.

Adding to 21550324401440 its reverse (4410442305512), we get a palindrome (25960766706952).

The spelling of 21550324401440 in words is "twenty-one trillion, five hundred fifty billion, three hundred twenty-four million, four hundred one thousand, four hundred forty".