21275666284800 has 216 divisors, whose sum is σ = 70309967762944. Its totient is φ = 5665767137280.

The previous prime is 21275666284799. The next prime is 21275666284867. The reversal of 21275666284800 is 848266657212.

It is a super-2 number, since 2×21275666284800² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13317729 + ... + 14829471.

Almost surely, 2^{21275666284800} is an apocalyptic number.

21275666284800 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 21275666284800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35154983881472).

21275666284800 is an abundant number, since it is smaller than the sum of its proper divisors (49034301478144).

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

21275666284800 is a wasteful number, since it uses less digits than its factorization.

21275666284800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1512505 (or 1512486 counting only the distinct ones).

The product of its (nonzero) digits is 15482880, while the sum is 57.

The spelling of 21275666284800 in words is "twenty-one trillion, two hundred seventy-five billion, six hundred sixty-six million, two hundred eighty-four thousand, eight hundred".