1381811 has 4 divisors (see below), whose sum is σ = 1463112. Its totient is φ = 1300512.

The previous prime is 1381769. The next prime is 1381819. The reversal of 1381811 is 1181831.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1381811 - 2⁶ = 1381747 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (1381819) 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 3 ways as a sum of consecutive naturals, for example, 40625 + ... + 40658.

It is an arithmetic number, because the mean of its divisors is an integer number (365778).

2^1381811 is an apocalyptic number.

1381811 is a deficient number, since it is larger than the sum of its proper divisors (81301).

1381811 is an equidigital number, since it uses as much as digits as its factorization.

1381811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81300.

The product of its digits is 192, while the sum is 23.

The square root of 1381811 is about 1175.5045725134. The cubic root of 1381811 is about 111.3823086028.

The spelling of 1381811 in words is "one million, three hundred eighty-one thousand, eight hundred eleven".