21229768817136 has 320 divisors, whose sum is σ = 69398981038080. Its totient is φ = 6150751200000.

The previous prime is 21229768817129. The next prime is 21229768817137. The reversal of 21229768817136 is 63171886792212.

21229768817136 is a `hidden beast` number, since 212 + 297 + 68 + 8 + 1 + 71 + 3 + 6 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21229768817137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 245982151 + ... + 246068441.

It is an arithmetic number, because the mean of its divisors is an integer number (216871815744).

Almost surely, 2^{21229768817136} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21229768817136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34699490519040).

21229768817136 is an abundant number, since it is smaller than the sum of its proper divisors (48169212220944).

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

21229768817136 is a wasteful number, since it uses less digits than its factorization.

21229768817136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88593 (or 88581 counting only the distinct ones).

The product of its digits is 24385536, while the sum is 63.

The spelling of 21229768817136 in words is "twenty-one trillion, two hundred twenty-nine billion, seven hundred sixty-eight million, eight hundred seventeen thousand, one hundred thirty-six".