6605566500661 has 16 divisors (see below), whose sum is σ = 7365178022400. Its totient is φ = 5892142341888.

The previous prime is 6605566500629. The next prime is 6605566500667. The reversal of 6605566500661 is 1660056655066.

It is a cyclic number.

It is not a de Polignac number, because 6605566500661 - 2⁵ = 6605566500629 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6605566500599 and 6605566500608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6605566500667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77452941 + ... + 77538178.

It is an arithmetic number, because the mean of its divisors is an integer number (460323626400).

Almost surely, 2^{6605566500661} is an apocalyptic number.

It is an amenable number.

6605566500661 is a deficient number, since it is larger than the sum of its proper divisors (759611521739).

6605566500661 is a wasteful number, since it uses less digits than its factorization.

6605566500661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154991268.

The product of its (nonzero) digits is 5832000, while the sum is 52.

The spelling of 6605566500661 in words is "six trillion, six hundred five billion, five hundred sixty-six million, five hundred thousand, six hundred sixty-one".