21545414400 has 108 divisors (see below), whose sum is σ = 71104419512. Its totient is φ = 5745438720.

The previous prime is 21545414393. The next prime is 21545414441. The reversal of 21545414400 is 441454512.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 541879 + ... + 580278.

Almost surely, 2^21545414400 is an apocalyptic number.

21545414400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21545414400 is an abundant number, since it is smaller than the sum of its proper divisors (49559005112).

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

21545414400 is a wasteful number, since it uses less digits than its factorization.

21545414400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1122186 (or 1122167 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 30.

Adding to 21545414400 its reverse (441454512), we get a palindrome (21986868912).

The spelling of 21545414400 in words is "twenty-one billion, five hundred forty-five million, four hundred fourteen thousand, four hundred".