21872865024 has 288 divisors, whose sum is σ = 66649443840. Its totient is φ = 7072800768.

The previous prime is 21872865019. The next prime is 21872865031. The reversal of 21872865024 is 42056827812.

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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 31 ways as a sum of consecutive naturals, for example, 33806269 + ... + 33806915.

It is an arithmetic number, because the mean of its divisors is an integer number (231421680).

Almost surely, 2^21872865024 is an apocalyptic number.

21872865024 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 21872865024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33324721920).

21872865024 is an abundant number, since it is smaller than the sum of its proper divisors (44776578816).

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

21872865024 is an equidigital number, since it uses as much as digits as its factorization.

21872865024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 812 (or 792 counting only the distinct ones).

The product of its (nonzero) digits is 430080, while the sum is 45.

The spelling of 21872865024 in words is "twenty-one billion, eight hundred seventy-two million, eight hundred sixty-five thousand, twenty-four".