21353405200 has 120 divisors (see below), whose sum is σ = 52489243400. Its totient is φ = 8345825280.

The previous prime is 21353405179. The next prime is 21353405209. The reversal of 21353405200 is 250435312.

It can be written as a sum of positive squares in 12 ways, for example, as 2073527296 + 19279877904 = 45536^2 + 138852^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (21353405209) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3179446 + ... + 3186154.

Almost surely, 2^21353405200 is an apocalyptic number.

21353405200 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 21353405200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26244621700).

21353405200 is an abundant number, since it is smaller than the sum of its proper divisors (31135838200).

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

21353405200 is a wasteful number, since it uses less digits than its factorization.

21353405200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6909 (or 6898 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 25.

The spelling of 21353405200 in words is "twenty-one billion, three hundred fifty-three million, four hundred five thousand, two hundred".