21275526516804 has 288 divisors, whose sum is σ = 68851027365120. Its totient is φ = 5392519888896.

The previous prime is 21275526516773. The next prime is 21275526516817. The reversal of 21275526516804 is 40861562557212.

21275526516804 is a `hidden beast` number, since 2 + 1 + 2 + 7 + 5 + 526 + 51 + 68 + 0 + 4 = 666.

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, 15371604 + ... + 16698420.

It is an arithmetic number, because the mean of its divisors is an integer number (239066067240).

Almost surely, 2^{21275526516804} 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 21275526516804, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34425513682560).

21275526516804 is an abundant number, since it is smaller than the sum of its proper divisors (47575500848316).

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

21275526516804 is a wasteful number, since it uses less digits than its factorization.

21275526516804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1327067 (or 1327062 counting only the distinct ones).

The product of its (nonzero) digits is 8064000, while the sum is 54.

The spelling of 21275526516804 in words is "twenty-one trillion, two hundred seventy-five billion, five hundred twenty-six million, five hundred sixteen thousand, eight hundred four".