2161943 has 4 divisors (see below), whose sum is σ = 2470800. Its totient is φ = 1853088.

The previous prime is 2161933. The next prime is 2161949. The reversal of 2161943 is 3491612.

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 2161943 - 2⁴ = 2161927 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 (2161949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154418 + ... + 154431.

It is an arithmetic number, because the mean of its divisors is an integer number (617700).

2^2161943 is an apocalyptic number.

2161943 is a deficient number, since it is larger than the sum of its proper divisors (308857).

2161943 is an equidigital number, since it uses as much as digits as its factorization.

2161943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308856.

The product of its digits is 1296, while the sum is 26.

The square root of 2161943 is about 1470.3547191069. The cubic root of 2161943 is about 129.3048296617.

The spelling of 2161943 in words is "two million, one hundred sixty-one thousand, nine hundred forty-three".