21040334400 has 84 divisors (see below), whose sum is σ = 69029846192. Its totient is φ = 5610754560.

The previous prime is 21040334389. The next prime is 21040334401. The reversal of 21040334400 is 443304012.

It is not an unprimeable number, because it can be changed into a prime (21040334401) 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, 2186902 + ... + 2196501.

Almost surely, 2^21040334400 is an apocalyptic number.

21040334400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21040334400 is an abundant number, since it is smaller than the sum of its proper divisors (47989511792).

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

21040334400 is a wasteful number, since it uses less digits than its factorization.

21040334400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4383428 (or 4383413 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

Adding to 21040334400 its reverse (443304012), we get a palindrome (21483638412).

The spelling of 21040334400 in words is "twenty-one billion, forty million, three hundred thirty-four thousand, four hundred".