21259123200 has 720 divisors, whose sum is σ = 89208415296. Its totient is φ = 4733337600.

The previous prime is 21259123183. The next prime is 21259123211. The reversal of 21259123200 is 232195212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (720).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 33062079 + ... + 33062721.

Almost surely, 2^21259123200 is an apocalyptic number.

21259123200 is a gapful number since it is divisible by the number (20) 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 21259123200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44604207648).

21259123200 is an abundant number, since it is smaller than the sum of its proper divisors (67949292096).

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

21259123200 is a wasteful number, since it uses less digits than its factorization.

21259123200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725 (or 701 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The spelling of 21259123200 in words is "twenty-one billion, two hundred fifty-nine million, one hundred twenty-three thousand, two hundred".