1091213 has 4 divisors (see below), whose sum is σ = 1155420. Its totient is φ = 1027008.

The previous prime is 1091191. The next prime is 1091219. The reversal of 1091213 is 3121901.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 797449 + 293764 = 893^2 + 542^2 .

It is a cyclic number.

It is not a de Polignac number, because 1091213 - 2⁶ = 1091149 is a prime.

It is a super-2 number, since 2×1091213² = 2381491622738, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 64189 = 1091213 / (1 + 0 + 9 + 1 + 2 + 1 + 3).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1091191 and 1091200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091219) 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, 32078 + ... + 32111.

It is an arithmetic number, because the mean of its divisors is an integer number (288855).

2^1091213 is an apocalyptic number.

It is an amenable number.

1091213 is a deficient number, since it is larger than the sum of its proper divisors (64207).

1091213 is an equidigital number, since it uses as much as digits as its factorization.

1091213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64206.

The product of its (nonzero) digits is 54, while the sum is 17.

The square root of 1091213 is about 1044.6114110041. The cubic root of 1091213 is about 102.9524083399.

The spelling of 1091213 in words is "one million, ninety-one thousand, two hundred thirteen".