21126800 has 30 divisors (see below), whose sum is σ = 50758098. Its totient is φ = 8450560.

The previous prime is 21126773. The next prime is 21126827. The reversal of 21126800 is 862112.

21126800 is nontrivially palindromic in base 14.

It is an interprime number because it is at equal distance from previous prime (21126773) and next prime (21126827).

It can be written as a sum of positive squares in 3 ways, for example, as 369664 + 20757136 = 608^2 + 4556^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 26009 + ... + 26808.

Almost surely, 2^21126800 is an apocalyptic number.

21126800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21126800 is an abundant number, since it is smaller than the sum of its proper divisors (29631298).

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

21126800 is a wasteful number, since it uses less digits than its factorization.

21126800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52835 (or 52824 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 21126800 is about 4596.3898877271. The cubic root of 21126800 is about 276.4465919755.

Adding to 21126800 its reverse (862112), we get a palindrome (21988912).

The spelling of 21126800 in words is "twenty-one million, one hundred twenty-six thousand, eight hundred".