21235231200 has 144 divisors (see below), whose sum is σ = 69733255536. Its totient is φ = 5612544000.

The previous prime is 21235231181. The next prime is 21235231217. The reversal of 21235231200 is 213253212.

It is a congruent number.

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, 232050 + ... + 310350.

It is an arithmetic number, because the mean of its divisors is an integer number (484258719).

Almost surely, 2^21235231200 is an apocalyptic number.

21235231200 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 21235231200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34866627768).

21235231200 is an abundant number, since it is smaller than the sum of its proper divisors (48498024336).

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

21235231200 is a wasteful number, since it uses less digits than its factorization.

21235231200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78437 (or 78424 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

Adding to 21235231200 its reverse (213253212), we get a palindrome (21448484412).

The spelling of 21235231200 in words is "twenty-one billion, two hundred thirty-five million, two hundred thirty-one thousand, two hundred".