6651560651566 has 4 divisors (see below), whose sum is σ = 9977340977352. Its totient is φ = 3325780325782.

The previous prime is 6651560651551. The next prime is 6651560651579.

6651560651566 is nontrivially palindromic in base 10.

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

It is a super-2 number, since 2×6651560651566² (a number of 26 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 6651560651566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1662890162890 + ... + 1662890162893.

It is an arithmetic number, because the mean of its divisors is an integer number (2494335244338).

Almost surely, 2^{6651560651566} is an apocalyptic number.

6651560651566 is a deficient number, since it is larger than the sum of its proper divisors (3325780325786).

6651560651566 is a wasteful number, since it uses less digits than its factorization.

6651560651566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3325780325785.

The product of its (nonzero) digits is 29160000, while the sum is 58.

The spelling of 6651560651566 in words is "six trillion, six hundred fifty-one billion, five hundred sixty million, six hundred fifty-one thousand, five hundred sixty-six".