1089861 has 8 divisors (see below), whose sum is σ = 1458240. Its totient is φ = 724032.

The previous prime is 1089841. The next prime is 1089863. The reversal of 1089861 is 1689801.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1089861 - 2¹⁵ = 1057093 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

1089861 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1089863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 880 + ... + 1718.

It is an arithmetic number, because the mean of its divisors is an integer number (182280).

2^1089861 is an apocalyptic number.

It is an amenable number.

1089861 is a deficient number, since it is larger than the sum of its proper divisors (368379).

1089861 is an equidigital number, since it uses as much as digits as its factorization.

1089861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1275.

The product of its (nonzero) digits is 3456, while the sum is 33.

The square root of 1089861 is about 1043.9640798418. The cubic root of 1089861 is about 102.9098718289.

The spelling of 1089861 in words is "one million, eighty-nine thousand, eight hundred sixty-one".