1381861 has 4 divisors (see below), whose sum is σ = 1488172. Its totient is φ = 1275552.

The previous prime is 1381859. The next prime is 1381871. The reversal of 1381861 is 1681831.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 516961 + 864900 = 719^2 + 930^2 .

It is a cyclic number.

It is not a de Polignac number, because 1381861 - 2¹ = 1381859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381871) 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, 53136 + ... + 53161.

It is an arithmetic number, because the mean of its divisors is an integer number (372043).

2^1381861 is an apocalyptic number.

It is an amenable number.

1381861 is a deficient number, since it is larger than the sum of its proper divisors (106311).

1381861 is a wasteful number, since it uses less digits than its factorization.

1381861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106310.

The product of its digits is 1152, while the sum is 28.

The square root of 1381861 is about 1175.5258397841. The cubic root of 1381861 is about 111.3836520206.

The spelling of 1381861 in words is "one million, three hundred eighty-one thousand, eight hundred sixty-one".