21036100 has 18 divisors (see below), whose sum is σ = 45648554. Its totient is φ = 8414400.

The previous prime is 21036083. The next prime is 21036131. The reversal of 21036100 is 163012.

It can be written as a sum of positive squares in 3 ways, for example, as 3041536 + 17994564 = 1744^2 + 4242^2 .

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, 105081 + ... + 105280.

Almost surely, 2^21036100 is an apocalyptic number.

21036100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21036100 is an abundant number, since it is smaller than the sum of its proper divisors (24612454).

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

21036100 is a wasteful number, since it uses less digits than its factorization.

21036100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210375 (or 210368 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 21036100 is about 4586.5128365677. The cubic root of 21036100 is about 276.0504178706.

Adding to 21036100 its reverse (163012), we get a palindrome (21199112).

The spelling of 21036100 in words is "twenty-one million, thirty-six thousand, one hundred".