1561601610605 has 16 divisors (see below), whose sum is σ = 1923637601280. Its totient is φ = 1216570762368.

The previous prime is 1561601610581. The next prime is 1561601610691. The reversal of 1561601610605 is 5060161061651.

It is a cyclic number.

It is not a de Polignac number, because 1561601610605 - 2²⁰ = 1561600562029 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27049397 + ... + 27107066.

It is an arithmetic number, because the mean of its divisors is an integer number (120227350080).

Almost surely, 2^{1561601610605} is an apocalyptic number.

It is an amenable number.

1561601610605 is a deficient number, since it is larger than the sum of its proper divisors (362035990675).

1561601610605 is an equidigital number, since it uses as much as digits as its factorization.

1561601610605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54156620.

The product of its (nonzero) digits is 32400, while the sum is 38.

The spelling of 1561601610605 in words is "one trillion, five hundred sixty-one billion, six hundred one million, six hundred ten thousand, six hundred five".