1091553 has 12 divisors (see below), whose sum is σ = 1547280. Its totient is φ = 684352.

The previous prime is 1091551. The next prime is 1091561. The reversal of 1091553 is 3551901.

It is not a de Polignac number, because 1091553 - 2¹ = 1091551 is a prime.

It is an Ulam number.

It is a Curzon number.

1091553 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1091551) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 238 + ... + 1496.

It is an arithmetic number, because the mean of its divisors is an integer number (128940).

2^1091553 is an apocalyptic number.

It is an amenable number.

1091553 is a deficient number, since it is larger than the sum of its proper divisors (455727).

1091553 is a wasteful number, since it uses less digits than its factorization.

1091553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1296 (or 1279 counting only the distinct ones).

The product of its (nonzero) digits is 675, while the sum is 24.

The square root of 1091553 is about 1044.7741382710. The cubic root of 1091553 is about 102.9630998621.

The spelling of 1091553 in words is "one million, ninety-one thousand, five hundred fifty-three".