66726980 has 24 divisors (see below), whose sum is σ = 140302680. Its totient is φ = 26657280.

The previous prime is 66726977. The next prime is 66726983. The reversal of 66726980 is 8962766.

66726980 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66726977) and next prime (66726983).

It can be written as a sum of positive squares in 4 ways, for example, as 369664 + 66357316 = 608^2 + 8146^2 .

It is a super-3 number, since 3×66726980³ (a number of 24 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (66726983) 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 7 ways as a sum of consecutive naturals, for example, 19820 + ... + 22940.

It is an arithmetic number, because the mean of its divisors is an integer number (5845945).

Almost surely, 2^66726980 is an apocalyptic number.

It is an amenable number.

66726980 is an abundant number, since it is smaller than the sum of its proper divisors (73575700).

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

66726980 is a wasteful number, since it uses less digits than its factorization.

66726980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4199 (or 4197 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 44.

The square root of 66726980 is about 8168.6583965790. The cubic root of 66726980 is about 405.6023754735.

The spelling of 66726980 in words is "sixty-six million, seven hundred twenty-six thousand, nine hundred eighty".