1161820 has 24 divisors (see below), whose sum is σ = 2662128. Its totient is φ = 422400.

The previous prime is 1161791. The next prime is 1161829. The reversal of 1161820 is 281611.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1161829) by changing a digit.

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, 2421 + ... + 2860.

It is an arithmetic number, because the mean of its divisors is an integer number (110922).

2^1161820 is an apocalyptic number.

1161820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1161820 is an abundant number, since it is smaller than the sum of its proper divisors (1500308).

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

1161820 is a wasteful number, since it uses less digits than its factorization.

1161820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5301 (or 5299 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 1161820 is about 1077.8775440652. The cubic root of 1161820 is about 105.1266800574.

It can be divided in two parts, 116 and 1820, that added together give a square (1936 = 44²).

The spelling of 1161820 in words is "one million, one hundred sixty-one thousand, eight hundred twenty".