2161738845571 has 4 divisors (see below), whose sum is σ = 2288899954152. Its totient is φ = 2034577736992.

The previous prime is 2161738845569. The next prime is 2161738845599. The reversal of 2161738845571 is 1755488371612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2161738845571 - 2¹ = 2161738845569 is a prime.

It is a super-2 number, since 2×2161738845571² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2161738845271) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63580554265 + ... + 63580554298.

It is an arithmetic number, because the mean of its divisors is an integer number (572224988538).

Almost surely, 2^{2161738845571} is an apocalyptic number.

2161738845571 is a deficient number, since it is larger than the sum of its proper divisors (127161108581).

2161738845571 is a wasteful number, since it uses less digits than its factorization.

2161738845571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127161108580.

The product of its digits is 11289600, while the sum is 58.

The spelling of 2161738845571 in words is "two trillion, one hundred sixty-one billion, seven hundred thirty-eight million, eight hundred forty-five thousand, five hundred seventy-one".