2161862865231 has 4 divisors (see below), whose sum is σ = 2882483820312. Its totient is φ = 1441241910152.

The previous prime is 2161862865203. The next prime is 2161862865257. The reversal of 2161862865231 is 1325682681612.

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 2161862865231 - 2¹⁹ = 2161862340943 is a prime.

It is a super-2 number, since 2×2161862865231² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161862865731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 360310477536 + ... + 360310477541.

It is an arithmetic number, because the mean of its divisors is an integer number (720620955078).

Almost surely, 2^{2161862865231} is an apocalyptic number.

2161862865231 is a deficient number, since it is larger than the sum of its proper divisors (720620955081).

2161862865231 is an equidigital number, since it uses as much as digits as its factorization.

2161862865231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720620955080.

The product of its digits is 1658880, while the sum is 51.

The spelling of 2161862865231 in words is "two trillion, one hundred sixty-one billion, eight hundred sixty-two million, eight hundred sixty-five thousand, two hundred thirty-one".