2161723893 has 32 divisors (see below), whose sum is σ = 3572916480. Its totient is φ = 1134243840.

The previous prime is 2161723873. The next prime is 2161723901. The reversal of 2161723893 is 3983271612.

It is not a de Polignac number, because 2161723893 - 2⁸ = 2161723637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161723813) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59208 + ... + 88481.

It is an arithmetic number, because the mean of its divisors is an integer number (111653640).

Almost surely, 2^2161723893 is an apocalyptic number.

It is an amenable number.

2161723893 is a deficient number, since it is larger than the sum of its proper divisors (1411192587).

2161723893 is a wasteful number, since it uses less digits than its factorization.

2161723893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147757.

The product of its digits is 108864, while the sum is 42.

The square root of 2161723893 is about 46494.3425913304. The cubic root of 2161723893 is about 1293.0046128403.

The spelling of 2161723893 in words is "two billion, one hundred sixty-one million, seven hundred twenty-three thousand, eight hundred ninety-three".