1121780 has 24 divisors (see below), whose sum is σ = 2570400. Its totient is φ = 407840.

The previous prime is 1121737. The next prime is 1121819. The reversal of 1121780 is 871211.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2330 + ... + 2769.

It is an arithmetic number, because the mean of its divisors is an integer number (107100).

2^1121780 is an apocalyptic number.

1121780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1121780 is an abundant number, since it is smaller than the sum of its proper divisors (1448620).

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

1121780 is a wasteful number, since it uses less digits than its factorization.

1121780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5119 (or 5117 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 20.

The square root of 1121780 is about 1059.1411615078. The cubic root of 1121780 is about 103.9048686288.

Adding to 1121780 its reverse (871211), we get a palindrome (1992991).

The spelling of 1121780 in words is "one million, one hundred twenty-one thousand, seven hundred eighty".