66522726400 has 405 divisors, whose sum is σ = 184585980663. Its totient is φ = 23769907200.

The previous prime is 66522726353. The next prime is 66522726409. The reversal of 66522726400 is 462722566.

The square root of 66522726400 is 257920.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 17146331136 + 49376395264 = 130944^2 + 222208^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (66522726409) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2145894385 + ... + 2145894415.

Almost surely, 2^66522726400 is an apocalyptic number.

66522726400 is the 257920-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66522726400

66522726400 is an abundant number, since it is smaller than the sum of its proper divisors (118063254263).

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

66522726400 is an equidigital number, since it uses as much as digits as its factorization.

66522726400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 40.

The spelling of 66522726400 in words is "sixty-six billion, five hundred twenty-two million, seven hundred twenty-six thousand, four hundred".