21258428324 has 72 divisors (see below), whose sum is σ = 43824755520. Its totient is φ = 8995783104.

The previous prime is 21258428239. The next prime is 21258428333. The reversal of 21258428324 is 42382485212.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7851779 + ... + 7854485.

It is an arithmetic number, because the mean of its divisors is an integer number (608677160).

Almost surely, 2^21258428324 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21258428324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21912377760).

21258428324 is an abundant number, since it is smaller than the sum of its proper divisors (22566327196).

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

21258428324 is a wasteful number, since it uses less digits than its factorization.

21258428324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3217 (or 3208 counting only the distinct ones).

The product of its digits is 245760, while the sum is 41.

The spelling of 21258428324 in words is "twenty-one billion, two hundred fifty-eight million, four hundred twenty-eight thousand, three hundred twenty-four".