2161561411061 has 16 divisors (see below), whose sum is σ = 2355993790080. Its totient is φ = 1971153956160.

The previous prime is 2161561411027. The next prime is 2161561411069. The reversal of 2161561411061 is 1601141651612.

It is a cyclic number.

It is not a de Polignac number, because 2161561411061 - 2¹⁰ = 2161561410037 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 (2161561411069) 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, 33620816 + ... + 33685046.

It is an arithmetic number, because the mean of its divisors is an integer number (147249611880).

Almost surely, 2^{2161561411061} is an apocalyptic number.

It is an amenable number.

2161561411061 is a deficient number, since it is larger than the sum of its proper divisors (194432379019).

2161561411061 is a wasteful number, since it uses less digits than its factorization.

2161561411061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95516.

The product of its (nonzero) digits is 8640, while the sum is 35.

The spelling of 2161561411061 in words is "two trillion, one hundred sixty-one billion, five hundred sixty-one million, four hundred eleven thousand, sixty-one".