1165921 has 2 divisors, whose sum is σ = 1165922. Its totient is φ = 1165920.

The previous prime is 1165919. The next prime is 1165933. The reversal of 1165921 is 1295611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 950625 + 215296 = 975^2 + 464^2 .

It is an emirp because it is prime and its reverse (1295611) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1165921 - 2¹ = 1165919 is a prime.

Together with 1165919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1165951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 582960 + 582961.

It is an arithmetic number, because the mean of its divisors is an integer number (582961).

2^1165921 is an apocalyptic number.

It is an amenable number.

1165921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1165921 is an equidigital number, since it uses as much as digits as its factorization.

1165921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 540, while the sum is 25.

The square root of 1165921 is about 1079.7782179689. The cubic root of 1165921 is about 105.2502270914.

The spelling of 1165921 in words is "one million, one hundred sixty-five thousand, nine hundred twenty-one".