66617812 has 6 divisors (see below), whose sum is σ = 116581178. Its totient is φ = 33308904.

The previous prime is 66617783. The next prime is 66617827. The reversal of 66617812 is 21871666.

66617812 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 59197636 + 7420176 = 7694^2 + 2724^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 8327223 + ... + 8327230.

Almost surely, 2^66617812 is an apocalyptic number.

It is an amenable number.

66617812 is a deficient number, since it is larger than the sum of its proper divisors (49963366).

66617812 is a wasteful number, since it uses less digits than its factorization.

66617812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16654457 (or 16654455 counting only the distinct ones).

The product of its digits is 24192, while the sum is 37.

The square root of 66617812 is about 8161.9735358552. The cubic root of 66617812 is about 405.3810608499.

The spelling of 66617812 in words is "sixty-six million, six hundred seventeen thousand, eight hundred twelve".