2165971 has 2 divisors, whose sum is σ = 2165972. Its totient is φ = 2165970.

The previous prime is 2165963. The next prime is 2166007. The reversal of 2165971 is 1795612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2165971 - 2³ = 2165963 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2165921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1082985 + 1082986.

It is an arithmetic number, because the mean of its divisors is an integer number (1082986).

2^2165971 is an apocalyptic number.

2165971 is a deficient number, since it is larger than the sum of its proper divisors (1).

2165971 is an equidigital number, since it uses as much as digits as its factorization.

2165971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 31.

The square root of 2165971 is about 1471.7238191998. The cubic root of 2165971 is about 129.3850841246.

It can be divided in two parts, 2165 and 971, that added together give a square (3136 = 56²).

The spelling of 2165971 in words is "two million, one hundred sixty-five thousand, nine hundred seventy-one".