21204111400 has 48 divisors (see below), whose sum is σ = 49320085500. Its totient is φ = 8478113280.

The previous prime is 21204111391. The next prime is 21204111413. The reversal of 21204111400 is 411140212.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 9466122436 + 11737988964 = 97294^2 + 108342^2 .

It is a super-2 number, since 2×21204111400² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 489004 + ... + 530596.

Almost surely, 2^21204111400 is an apocalyptic number.

21204111400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21204111400 is an abundant number, since it is smaller than the sum of its proper divisors (28115974100).

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

21204111400 is a wasteful number, since it uses less digits than its factorization.

21204111400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44158 (or 44149 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21204111400 its reverse (411140212), we get a palindrome (21615251612).

The spelling of 21204111400 in words is "twenty-one billion, two hundred four million, one hundred eleven thousand, four hundred".