555665666566566 has 128 divisors (see below), whose sum is σ = 1166082256797696. Its totient is φ = 176189115548160.

The previous prime is 555665666566553. The next prime is 555665666566649. The reversal of 555665666566566 is 665665666566555.

555665666566566 is a nontrivial binomial coefficient, being equal to C(33336637, 2).

It is a super-2 number, since 2×555665666566566² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 88608778011 + ... + 88608784281.

It is an arithmetic number, because the mean of its divisors is an integer number (9110017631232).

Almost surely, 2^{555665666566566} is an apocalyptic number.

555665666566566 is the 33336636-th triangular number.

555665666566566 is an abundant number, since it is smaller than the sum of its proper divisors (610416590231130).

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

555665666566566 is a wasteful number, since it uses less digits than its factorization.

555665666566566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11266.

The product of its digits is 157464000000, while the sum is 84.

The spelling of 555665666566566 in words is "five hundred fifty-five trillion, six hundred sixty-five billion, six hundred sixty-six million, five hundred sixty-six thousand, five hundred sixty-six".