1181220 has 24 divisors (see below), whose sum is σ = 3307584. Its totient is φ = 314976.

The previous prime is 1181209. The next prime is 1181237. The reversal of 1181220 is 221811.

1181220 is nontrivially palindromic in base 8.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1181220.

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, 9784 + ... + 9903.

It is an arithmetic number, because the mean of its divisors is an integer number (137816).

2^1181220 is an apocalyptic number.

1181220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1181220 is an abundant number, since it is smaller than the sum of its proper divisors (2126364).

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

1181220 is a wasteful number, since it uses less digits than its factorization.

1181220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19699 (or 19697 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

The square root of 1181220 is about 1086.8394545654. The cubic root of 1181220 is about 105.7085860783.

The spelling of 1181220 in words is "one million, one hundred eighty-one thousand, two hundred twenty".