66390736896 has 405 divisors, whose sum is σ = 214322622969. Its totient is φ = 19788595200.

The previous prime is 66390736859. The next prime is 66390736897. The reversal of 66390736896 is 69863709366.

The square root of 66390736896 is 257664.

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

It can be written as a sum of positive squares in only one way, i.e., 2158903296 + 64231833600 = 46464^2 + 253440^2 .

It is not an unprimeable number, because it can be changed into a prime (66390736897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1088372706 + ... + 1088372766.

Almost surely, 2^66390736896 is an apocalyptic number.

66390736896 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

66390736896 is the 257664-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66390736896

66390736896 is an abundant number, since it is smaller than the sum of its proper divisors (147931886073).

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

66390736896 is an equidigital number, since it uses as much as digits as its factorization.

66390736896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 52907904, while the sum is 63.

The spelling of 66390736896 in words is "sixty-six billion, three hundred ninety million, seven hundred thirty-six thousand, eight hundred ninety-six".