2161723915 has 8 divisors (see below), whose sum is σ = 2793612528. Its totient is φ = 1596349920.

The previous prime is 2161723913. The next prime is 2161723919. The reversal of 2161723915 is 5193271612.

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

It is not a de Polignac number, because 2161723915 - 2¹ = 2161723913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2161723913) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16628581 + ... + 16628710.

It is an arithmetic number, because the mean of its divisors is an integer number (349201566).

Almost surely, 2^2161723915 is an apocalyptic number.

2161723915 is a deficient number, since it is larger than the sum of its proper divisors (631888613).

2161723915 is a wasteful number, since it uses less digits than its factorization.

2161723915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33257309.

The product of its digits is 22680, while the sum is 37.

The square root of 2161723915 is about 46494.3428279183. The cubic root of 2161723915 is about 1293.0046172267.

The spelling of 2161723915 in words is "two billion, one hundred sixty-one million, seven hundred twenty-three thousand, nine hundred fifteen".