1091055 has 16 divisors (see below), whose sum is σ = 1995264. Its totient is φ = 498720.

The previous prime is 1091053. The next prime is 1091059. The reversal of 1091055 is 5501901.

It is a happy number.

It is not a de Polignac number, because 1091055 - 2¹ = 1091053 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091053) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5091 + ... + 5300.

It is an arithmetic number, because the mean of its divisors is an integer number (124704).

2^1091055 is an apocalyptic number.

1091055 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1091055 is a deficient number, since it is larger than the sum of its proper divisors (904209).

1091055 is a wasteful number, since it uses less digits than its factorization.

1091055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10406.

The product of its (nonzero) digits is 225, while the sum is 21.

The square root of 1091055 is about 1044.5357820582. The cubic root of 1091055 is about 102.9474391708.

Adding to 1091055 its reverse (5501901), we get a palindrome (6592956).

The spelling of 1091055 in words is "one million, ninety-one thousand, fifty-five".