21113540053600 has 144 divisors (see below), whose sum is σ = 52007393626272. Its totient is φ = 8369417871360.

The previous prime is 21113540053577. The next prime is 21113540053601. The reversal of 21113540053600 is 635004531112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113540053601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 803914069 + ... + 803940331.

It is an arithmetic number, because the mean of its divisors is an integer number (361162455738).

Almost surely, 2^{21113540053600} is an apocalyptic number.

21113540053600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21113540053600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26003696813136).

21113540053600 is an abundant number, since it is smaller than the sum of its proper divisors (30893853572672).

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

21113540053600 is a wasteful number, since it uses less digits than its factorization.

21113540053600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35289 (or 35276 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

Adding to 21113540053600 its reverse (635004531112), we get a palindrome (21748544584712).

The spelling of 21113540053600 in words is "twenty-one trillion, one hundred thirteen billion, five hundred forty million, fifty-three thousand, six hundred".