6651105651561 has 16 divisors (see below), whose sum is σ = 10135328998784. Its totient is φ = 3800515227264.

The previous prime is 6651105651551. The next prime is 6651105651571. The reversal of 6651105651561 is 1651565011566.

It is an interprime number because it is at equal distance from previous prime (6651105651551) and next prime (6651105651571).

It is not a de Polignac number, because 6651105651561 - 2³¹ = 6648958167913 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6651105651561.

It is not an unprimeable number, because it can be changed into a prime (6651105651551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4153906 + ... + 5527851.

It is an arithmetic number, because the mean of its divisors is an integer number (633458062424).

Almost surely, 2^{6651105651561} is an apocalyptic number.

It is an amenable number.

6651105651561 is a deficient number, since it is larger than the sum of its proper divisors (3484223347223).

6651105651561 is a wasteful number, since it uses less digits than its factorization.

6651105651561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9714480.

The product of its (nonzero) digits is 810000, while the sum is 48.

The spelling of 6651105651561 in words is "six trillion, six hundred fifty-one billion, one hundred five million, six hundred fifty-one thousand, five hundred sixty-one".