1181801 has 4 divisors (see below), whose sum is σ = 1193604. Its totient is φ = 1170000.

The previous prime is 1181777. The next prime is 1181839. The reversal of 1181801 is 1081811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1081811 = 101 ⋅10711.

It can be written as a sum of positive squares in 2 ways, for example, as 1048576 + 133225 = 1024^2 + 365^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1181801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1181881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5750 + ... + 5951.

It is an arithmetic number, because the mean of its divisors is an integer number (298401).

2^1181801 is an apocalyptic number.

It is an amenable number.

1181801 is a deficient number, since it is larger than the sum of its proper divisors (11803).

1181801 is a wasteful number, since it uses less digits than its factorization.

1181801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11802.

The product of its (nonzero) digits is 64, while the sum is 20.

The square root of 1181801 is about 1087.1067104935. The cubic root of 1181801 is about 105.7259146656.

It can be divided in two parts, 11 and 81801, that multiplied together give a triangular number (899811 = T₁₃₄₁).

The spelling of 1181801 in words is "one million, one hundred eighty-one thousand, eight hundred one".