66806386 has 8 divisors (see below), whose sum is σ = 102918060. Its totient is φ = 32500368.

The previous prime is 66806359. The next prime is 66806387. The reversal of 66806386 is 68360866.

It can be written as a sum of positive squares in 2 ways, for example, as 45360225 + 21446161 = 6735^2 + 4631^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (66806387) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 451321 + ... + 451468.

Almost surely, 2^66806386 is an apocalyptic number.

66806386 is a deficient number, since it is larger than the sum of its proper divisors (36111674).

66806386 is a wasteful number, since it uses less digits than its factorization.

66806386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 902828.

The product of its (nonzero) digits is 248832, while the sum is 43.

The square root of 66806386 is about 8173.5173579066. The cubic root of 66806386 is about 405.7632024482.

The spelling of 66806386 in words is "sixty-six million, eight hundred six thousand, three hundred eighty-six".