66555683426 has 4 divisors (see below), whose sum is σ = 99833525142. Its totient is φ = 33277841712.

The previous prime is 66555683423. The next prime is 66555683459. The reversal of 66555683426 is 62438655566.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 52257502801 + 14298180625 = 228599^2 + 119575^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66555683423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16638920855 + ... + 16638920858.

Almost surely, 2^66555683426 is an apocalyptic number.

66555683426 is a deficient number, since it is larger than the sum of its proper divisors (33277841716).

66555683426 is a wasteful number, since it uses less digits than its factorization.

66555683426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33277841715.

The product of its digits is 31104000, while the sum is 56.

The spelling of 66555683426 in words is "sixty-six billion, five hundred fifty-five million, six hundred eighty-three thousand, four hundred twenty-six".