21041400 has 48 divisors (see below), whose sum is σ = 65230200. Its totient is φ = 5610880.

The previous prime is 21041387. The next prime is 21041407. The reversal of 21041400 is 414012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21041407) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16935 + ... + 18134.

Almost surely, 2^21041400 is an apocalyptic number.

21041400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21041400 is an abundant number, since it is smaller than the sum of its proper divisors (44188800).

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

21041400 is a wasteful number, since it uses less digits than its factorization.

21041400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35088 (or 35079 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21041400 is about 4587.0905811854. The cubic root of 21041400 is about 276.0735993595.

Adding to 21041400 its reverse (414012), we get a palindrome (21455412).

The spelling of 21041400 in words is "twenty-one million, forty-one thousand, four hundred".