2161665229 has 8 divisors (see below), whose sum is σ = 2200504320. Its totient is φ = 2123113200.

The previous prime is 2161665227. The next prime is 2161665241. The reversal of 2161665229 is 9225661612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2161665229 - 2¹ = 2161665227 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2161665191 and 2161665200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161665227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56542 + ... + 86719.

It is an arithmetic number, because the mean of its divisors is an integer number (275063040).

Almost surely, 2^2161665229 is an apocalyptic number.

It is an amenable number.

2161665229 is a deficient number, since it is larger than the sum of its proper divisors (38839091).

2161665229 is a wasteful number, since it uses less digits than its factorization.

2161665229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143531.

The product of its digits is 77760, while the sum is 40.

The square root of 2161665229 is about 46493.7117145964. The cubic root of 2161665229 is about 1292.9929163869.

The spelling of 2161665229 in words is "two billion, one hundred sixty-one million, six hundred sixty-five thousand, two hundred twenty-nine".