1091965 has 12 divisors (see below), whose sum is σ = 1524636. Its totient is φ = 748608.

The previous prime is 1091957. The next prime is 1091983. The reversal of 1091965 is 5691901.

It can be written as a sum of positive squares in 2 ways, for example, as 582169 + 509796 = 763^2 + 714^2 .

It is not a de Polignac number, because 1091965 - 2³ = 1091957 is a prime.

It is a super-2 number, since 2×1091965² = 2384775122450, which contains 22 as substring.

It is a Duffinian number.

1091965 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1984 + ... + 2473.

It is an arithmetic number, because the mean of its divisors is an integer number (127053).

2^1091965 is an apocalyptic number.

It is an amenable number.

1091965 is a deficient number, since it is larger than the sum of its proper divisors (432671).

1091965 is an equidigital number, since it uses as much as digits as its factorization.

1091965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4476 (or 4469 counting only the distinct ones).

The product of its (nonzero) digits is 2430, while the sum is 31.

The square root of 1091965 is about 1044.9712914717. The cubic root of 1091965 is about 102.9760524965.

It can be divided in two parts, 109 and 1965, that multiplied together give a triangular number (214185 = T₆₅₄).

The spelling of 1091965 in words is "one million, ninety-one thousand, nine hundred sixty-five".