1089691 has 4 divisors (see below), whose sum is σ = 1093984. Its totient is φ = 1085400.

The previous prime is 1089679. The next prime is 1089703. The reversal of 1089691 is 1969801.

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

It is an interprime number because it is at equal distance from previous prime (1089679) and next prime (1089703).

It is a cyclic number.

It is not a de Polignac number, because 1089691 - 2⁷ = 1089563 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1089611) 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, 1740 + ... + 2281.

It is an arithmetic number, because the mean of its divisors is an integer number (273496).

2^1089691 is an apocalyptic number.

1089691 is a deficient number, since it is larger than the sum of its proper divisors (4293).

1089691 is an equidigital number, since it uses as much as digits as its factorization.

1089691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4292.

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

The square root of 1089691 is about 1043.8826562406. The cubic root of 1089691 is about 102.9045208138.

The spelling of 1089691 in words is "one million, eighty-nine thousand, six hundred ninety-one".