1091816 has 32 divisors (see below), whose sum is σ = 2354400. Its totient is φ = 469440.

The previous prime is 1091809. The next prime is 1091837. The reversal of 1091816 is 6181901.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1346 + ... + 1998.

It is an arithmetic number, because the mean of its divisors is an integer number (73575).

2^1091816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1091816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1177200).

1091816 is an abundant number, since it is smaller than the sum of its proper divisors (1262584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1091816 is a wasteful number, since it uses less digits than its factorization.

1091816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 685 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 26.

The square root of 1091816 is about 1044.8999952149. The cubic root of 1091816 is about 102.9713685461.

The spelling of 1091816 in words is "one million, ninety-one thousand, eight hundred sixteen".