66681010 has 32 divisors (see below), whose sum is σ = 131274432. Its totient is φ = 24185280.

The previous prime is 66681007. The next prime is 66681011. The reversal of 66681010 is 1018666.

It is a self number, because there is not a number n which added to its sum of digits gives 66681010.

It is not an unprimeable number, because it can be changed into a prime (66681011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80217 + ... + 81043.

It is an arithmetic number, because the mean of its divisors is an integer number (4102326).

Almost surely, 2^66681010 is an apocalyptic number.

66681010 is a deficient number, since it is larger than the sum of its proper divisors (64593422).

66681010 is a wasteful number, since it uses less digits than its factorization.

66681010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1578.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 66681010 is about 8165.8441082352. The cubic root of 66681010 is about 405.5092106365.

Adding to 66681010 its reverse (1018666), we get a palindrome (67699676).

The spelling of 66681010 in words is "sixty-six million, six hundred eighty-one thousand, ten".