1091869 has 2 divisors, whose sum is σ = 1091870. Its totient is φ = 1091868.

The previous prime is 1091863. The next prime is 1091887. The reversal of 1091869 is 9681901.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 580644 + 511225 = 762^2 + 715^2 .

It is a cyclic number.

It is not a de Polignac number, because 1091869 - 2⁵ = 1091837 is a prime.

It is a super-2 number, since 2×1091869² = 2384355826322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1091863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545934 + 545935.

It is an arithmetic number, because the mean of its divisors is an integer number (545935).

2^1091869 is an apocalyptic number.

It is an amenable number.

1091869 is a deficient number, since it is larger than the sum of its proper divisors (1).

1091869 is an equidigital number, since it uses as much as digits as its factorization.

1091869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 1091869 is about 1044.9253561858. The cubic root of 1091869 is about 102.9730346981.

It can be divided in two parts, 10 and 91869, that multiplied together give a triangular number (918690 = T₁₃₅₅).

The spelling of 1091869 in words is "one million, ninety-one thousand, eight hundred sixty-nine".