21144104801280 has 1056 divisors, whose sum is σ = 81681957826560. Its totient is φ = 5227741347840.

The previous prime is 21144104801257. The next prime is 21144104801311. The reversal of 21144104801280 is 8210840144112.

It is a happy number.

21144104801280 is a `hidden beast` number, since 2 + 1 + 1 + 44 + 10 + 480 + 128 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1111025365 + ... + 1111044395.

Almost surely, 2^{21144104801280} is an apocalyptic number.

21144104801280 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 21144104801280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40840978913280).

21144104801280 is an abundant number, since it is smaller than the sum of its proper divisors (60537853025280).

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

21144104801280 is a wasteful number, since it uses less digits than its factorization.

21144104801280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19137 (or 19107 counting only the distinct ones).

The product of its (nonzero) digits is 16384, while the sum is 36.

Adding to 21144104801280 its reverse (8210840144112), we get a palindrome (29354944945392).

The spelling of 21144104801280 in words is "twenty-one trillion, one hundred forty-four billion, one hundred four million, eight hundred one thousand, two hundred eighty".