21307393224 has 256 divisors, whose sum is σ = 68932684800. Its totient is φ = 6038544384.

The previous prime is 21307393187. The next prime is 21307393253. The reversal of 21307393224 is 42239370312.

21307393224 is a `hidden beast` number, since 21 + 307 + 3 + 9 + 322 + 4 = 666.

It is a super-2 number, since 2×21307393224² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2238844 + ... + 2248340.

It is an arithmetic number, because the mean of its divisors is an integer number (269268300).

Almost surely, 2^21307393224 is an apocalyptic number.

21307393224 is a gapful number since it is divisible by the number (24) 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 21307393224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34466342400).

21307393224 is an abundant number, since it is smaller than the sum of its proper divisors (47625291576).

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

21307393224 is a wasteful number, since it uses less digits than its factorization.

21307393224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9589 (or 9579 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 36.

The spelling of 21307393224 in words is "twenty-one billion, three hundred seven million, three hundred ninety-three thousand, two hundred twenty-four".