21744723020 has 24 divisors (see below), whose sum is σ = 47649307104. Its totient is φ = 8319719936.

The previous prime is 21744722963. The next prime is 21744723023. The reversal of 21744723020 is 2032744712.

It is not an unprimeable number, because it can be changed into a prime (21744723023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23635109 + ... + 23636028.

It is an arithmetic number, because the mean of its divisors is an integer number (1985387796).

Almost surely, 2^21744723020 is an apocalyptic number.

21744723020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21744723020 is an abundant number, since it is smaller than the sum of its proper divisors (25904584084).

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

21744723020 is a wasteful number, since it uses less digits than its factorization.

21744723020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47271169 (or 47271167 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 32.

The spelling of 21744723020 in words is "twenty-one billion, seven hundred forty-four million, seven hundred twenty-three thousand, twenty".