1089561 has 16 divisors (see below), whose sum is σ = 1603008. Its totient is φ = 652800.

The previous prime is 1089551. The next prime is 1089563. The reversal of 1089561 is 1659801.

It is a happy number.

It is not a de Polignac number, because 1089561 - 2⁶ = 1089497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1089563) 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, 4401 + ... + 4641.

It is an arithmetic number, because the mean of its divisors is an integer number (100188).

2^1089561 is an apocalyptic number.

1089561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1089561 is a deficient number, since it is larger than the sum of its proper divisors (513447).

1089561 is a wasteful number, since it uses less digits than its factorization.

1089561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392.

The product of its (nonzero) digits is 2160, while the sum is 30.

The square root of 1089561 is about 1043.8203868482. The cubic root of 1089561 is about 102.9004284856.

It can be divided in two parts, 108 and 9561, that added together give a palindrome (9669).

The spelling of 1089561 in words is "one million, eighty-nine thousand, five hundred sixty-one".