1091916 has 54 divisors (see below), whose sum is σ = 3215940. Its totient is φ = 311472.

The previous prime is 1091887. The next prime is 1091917. The reversal of 1091916 is 6191901.

It is a self number, because there is not a number n which added to its sum of digits gives 1091916.

It is not an unprimeable number, because it can be changed into a prime (1091917) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1455 + ... + 2073.

2^1091916 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 1091916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1607970).

1091916 is an abundant number, since it is smaller than the sum of its proper divisors (2124024).

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

1091916 is a wasteful number, since it uses less digits than its factorization.

1091916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643 (or 631 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 27.

The square root of 1091916 is about 1044.9478455885. The cubic root of 1091916 is about 102.9745121840.

It can be divided in two parts, 109 and 1916, that added together give a square (2025 = 45²).

The spelling of 1091916 in words is "one million, ninety-one thousand, nine hundred sixteen".