2161704823 has 2 divisors, whose sum is σ = 2161704824. Its totient is φ = 2161704822.

The previous prime is 2161704821. The next prime is 2161704847. The reversal of 2161704823 is 3284071612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2161704823 - 2¹ = 2161704821 is a prime.

It is a super-2 number, since 2×2161704823² = 9345935483562922658, which contains 22 as substring.

Together with 2161704821, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2161704821) 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 as a sum of consecutive naturals, namely, 1080852411 + 1080852412.

It is an arithmetic number, because the mean of its divisors is an integer number (1080852412).

Almost surely, 2^2161704823 is an apocalyptic number.

2161704823 is a deficient number, since it is larger than the sum of its proper divisors (1).

2161704823 is an equidigital number, since it uses as much as digits as its factorization.

2161704823 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 2161704823 is about 46494.1375121638. The cubic root of 2161704823 is about 1293.0008106788. Note that the first 3 decimals are identical.

The spelling of 2161704823 in words is "two billion, one hundred sixty-one million, seven hundred four thousand, eight hundred twenty-three".