2161955 has 4 divisors (see below), whose sum is σ = 2594352. Its totient is φ = 1729560.

The previous prime is 2161949. The next prime is 2161963. The reversal of 2161955 is 5591612.

2161955 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 2161955 - 2⁸ = 2161699 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 216191 + ... + 216200.

It is an arithmetic number, because the mean of its divisors is an integer number (648588).

2^2161955 is an apocalyptic number.

2161955 is a deficient number, since it is larger than the sum of its proper divisors (432397).

2161955 is an equidigital number, since it uses as much as digits as its factorization.

2161955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432396.

The product of its digits is 2700, while the sum is 29.

The square root of 2161955 is about 1470.3587997492. The cubic root of 2161955 is about 129.3050688994.

The spelling of 2161955 in words is "two million, one hundred sixty-one thousand, nine hundred fifty-five".