21071300 has 18 divisors (see below), whose sum is σ = 45724938. Its totient is φ = 8428480.

The previous prime is 21071287. The next prime is 21071321. The reversal of 21071300 is 317012.

It can be written as a sum of positive squares in 3 ways, for example, as 295936 + 20775364 = 544^2 + 4558^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105257 + ... + 105456.

Almost surely, 2^21071300 is an apocalyptic number.

21071300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21071300 is an abundant number, since it is smaller than the sum of its proper divisors (24653638).

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

21071300 is a wasteful number, since it uses less digits than its factorization.

21071300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210727 (or 210720 counting only the distinct ones).

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 21071300 is about 4590.3485706425. The cubic root of 21071300 is about 276.2043050755.

Adding to 21071300 its reverse (317012), we get a palindrome (21388312).

The spelling of 21071300 in words is "twenty-one million, seventy-one thousand, three hundred".