21242443320 has 128 divisors (see below), whose sum is σ = 80923622400. Its totient is φ = 4855413888.

The previous prime is 21242443319. The next prime is 21242443337. The reversal of 21242443320 is 2334424212.

21242443320 is a `hidden beast` number, since 212 + 4 + 2 + 443 + 3 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1397364 + ... + 1412483.

It is an arithmetic number, because the mean of its divisors is an integer number (632215800).

Almost surely, 2^21242443320 is an apocalyptic number.

21242443320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21242443320 is an abundant number, since it is smaller than the sum of its proper divisors (59681179080).

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

21242443320 is a wasteful number, since it uses less digits than its factorization.

21242443320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2809874 (or 2809864 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21242443320 its reverse (2334424212), we get a palindrome (23576867532).

The spelling of 21242443320 in words is "twenty-one billion, two hundred forty-two million, four hundred forty-three thousand, three hundred twenty".