21243854080 has 36 divisors (see below), whose sum is σ = 50885672292. Its totient is φ = 8497541120.

The previous prime is 21243854053. The next prime is 21243854101. The reversal of 21243854080 is 8045834212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 16131032064 + 5112822016 = 127008^2 + 71504^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8297101 + ... + 8299660.

It is an arithmetic number, because the mean of its divisors is an integer number (1413490897).

Almost surely, 2^21243854080 is an apocalyptic number.

21243854080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21243854080 is an abundant number, since it is smaller than the sum of its proper divisors (29641818212).

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

21243854080 is an equidigital number, since it uses as much as digits as its factorization.

21243854080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16596782 (or 16596768 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 37.

The spelling of 21243854080 in words is "twenty-one billion, two hundred forty-three million, eight hundred fifty-four thousand, eighty".