21663204233360 has 80 divisors (see below), whose sum is σ = 51862747290480. Its totient is φ = 8410130350080.

The previous prime is 21663204233347. The next prime is 21663204233389. The reversal of 21663204233360 is 6333240236612.

It can be written as a sum of positive squares in 8 ways, for example, as 7824417350656 + 13838786882704 = 2797216^2 + 3720052^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (41).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16477415 + ... + 17743494.

It is an arithmetic number, because the mean of its divisors is an integer number (648284341131).

Almost surely, 2^{21663204233360} is an apocalyptic number.

21663204233360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21663204233360 is an abundant number, since it is smaller than the sum of its proper divisors (30199543057120).

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

21663204233360 is a wasteful number, since it uses less digits than its factorization.

21663204233360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34221156 (or 34221150 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 41.

Adding to 21663204233360 its reverse (6333240236612), we get a palindrome (27996444469972).

The spelling of 21663204233360 in words is "twenty-one trillion, six hundred sixty-three billion, two hundred four million, two hundred thirty-three thousand, three hundred sixty".