6556616615566 has 4 divisors (see below), whose sum is σ = 9834924923352. Its totient is φ = 3278308307782.

The previous prime is 6556616615533. The next prime is 6556616615569. The reversal of 6556616615566 is 6655166166556.

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

It is a super-2 number, since 2×6556616615566² (a number of 26 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6556616615498 and 6556616615507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6556616615569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1639154153890 + ... + 1639154153893.

It is an arithmetic number, because the mean of its divisors is an integer number (2458731230838).

Almost surely, 2^{6556616615566} is an apocalyptic number.

6556616615566 is a deficient number, since it is larger than the sum of its proper divisors (3278308307786).

6556616615566 is a wasteful number, since it uses less digits than its factorization.

6556616615566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3278308307785.

The product of its digits is 174960000, while the sum is 64.

The spelling of 6556616615566 in words is "six trillion, five hundred fifty-six billion, six hundred sixteen million, six hundred fifteen thousand, five hundred sixty-six".