1118021 has 2 divisors, whose sum is σ = 1118022. Its totient is φ = 1118020.

The previous prime is 1118011. The next prime is 1118023. The reversal of 1118021 is 1208111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1060900 + 57121 = 1030^2 + 239^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1118021 is a prime.

Together with 1118023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1117987 and 1118005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1118023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 559010 + 559011.

It is an arithmetic number, because the mean of its divisors is an integer number (559011).

2^1118021 is an apocalyptic number.

It is an amenable number.

1118021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1118021 is an equidigital number, since it uses as much as digits as its factorization.

1118021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 14.

The square root of 1118021 is about 1057.3651214221. The cubic root of 1118021 is about 103.7886796312.

The spelling of 1118021 in words is "one million, one hundred eighteen thousand, twenty-one".