21265300 has 72 divisors (see below), whose sum is σ = 55871424. Its totient is φ = 6858240.

The previous prime is 21265273. The next prime is 21265301. The reversal of 21265300 is 356212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21265301) 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, 11007 + ... + 12793.

It is an arithmetic number, because the mean of its divisors is an integer number (775992).

Almost surely, 2^21265300 is an apocalyptic number.

21265300 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 21265300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27935712).

21265300 is an abundant number, since it is smaller than the sum of its proper divisors (34606124).

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

21265300 is a wasteful number, since it uses less digits than its factorization.

21265300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1825 (or 1818 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 21265300 is about 4611.4314480430. The cubic root of 21265300 is about 277.0493727890.

The spelling of 21265300 in words is "twenty-one million, two hundred sixty-five thousand, three hundred".