2161707215 has 4 divisors (see below), whose sum is σ = 2594048664. Its totient is φ = 1729365768.

The previous prime is 2161707211. The next prime is 2161707239. The reversal of 2161707215 is 5127071612.

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 2161707215 - 2² = 2161707211 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 (2161707211) 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 3 ways as a sum of consecutive naturals, for example, 216170717 + ... + 216170726.

It is an arithmetic number, because the mean of its divisors is an integer number (648512166).

Almost surely, 2^2161707215 is an apocalyptic number.

2161707215 is a deficient number, since it is larger than the sum of its proper divisors (432341449).

2161707215 is an equidigital number, since it uses as much as digits as its factorization.

2161707215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432341448.

The product of its (nonzero) digits is 5880, while the sum is 32.

The square root of 2161707215 is about 46494.1632358299. The cubic root of 2161707215 is about 1293.0012875951.

Adding to 2161707215 its reverse (5127071612), we get a palindrome (7288778827).

The spelling of 2161707215 in words is "two billion, one hundred sixty-one million, seven hundred seven thousand, two hundred fifteen".