1655601105661 has 6 divisors (see below), whose sum is σ = 1758718129850. Its totient is φ = 1558212805056.

The previous prime is 1655601105617. The next prime is 1655601105689. The reversal of 1655601105661 is 1665011065561.

It can be written as a sum of positive squares in 3 ways, for example, as 794426385636 + 861174720025 = 891306^2 + 927995^2 .

It is not a de Polignac number, because 1655601105661 - 2²⁵ = 1655567551229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1655601100661) 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 5 ways as a sum of consecutive naturals, for example, 2864361486 + ... + 2864362063.

Almost surely, 2^{1655601105661} is an apocalyptic number.

It is an amenable number.

1655601105661 is a deficient number, since it is larger than the sum of its proper divisors (103117024189).

1655601105661 is an equidigital number, since it uses as much as digits as its factorization.

1655601105661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5728723583 (or 5728723566 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 43.

The spelling of 1655601105661 in words is "one trillion, six hundred fifty-five billion, six hundred one million, one hundred five thousand, six hundred sixty-one".