1091280 has 40 divisors (see below), whose sum is σ = 3383712. Its totient is φ = 290944.

The previous prime is 1091273. The next prime is 1091287. The reversal of 1091280 is 821901.

It is an interprime number because it is at equal distance from previous prime (1091273) and next prime (1091287).

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2034 + ... + 2513.

2^1091280 is an apocalyptic number.

1091280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1091280 is an abundant number, since it is smaller than the sum of its proper divisors (2292432).

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

1091280 is a wasteful number, since it uses less digits than its factorization.

1091280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4563 (or 4557 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 1091280 is about 1044.6434798533. The cubic root of 1091280 is about 102.9545153743.

The spelling of 1091280 in words is "one million, ninety-one thousand, two hundred eighty".