665126626621566 has 8 divisors (see below), whose sum is σ = 1330253253243144. Its totient is φ = 221708875540520.

The previous prime is 665126626621549. The next prime is 665126626621609.

665126626621566 is nontrivially palindromic in base 10.

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

665126626621566 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 665126626621497 and 665126626621506.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55427218885125 + ... + 55427218885136.

It is an arithmetic number, because the mean of its divisors is an integer number (166281656655393).

Almost surely, 2^{665126626621566} is an apocalyptic number.

665126626621566 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

665126626621566 is a wasteful number, since it uses less digits than its factorization.

665126626621566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110854437770266.

The product of its digits is 335923200, while the sum is 66.

The spelling of 665126626621566 in words is "six hundred sixty-five trillion, one hundred twenty-six billion, six hundred twenty-six million, six hundred twenty-one thousand, five hundred sixty-six".