1861369 has 4 divisors (see below), whose sum is σ = 1866996. Its totient is φ = 1855744.

The previous prime is 1861351. The next prime is 1861397. The reversal of 1861369 is 9631681.

1861369 is nontrivially palindromic in base 5.

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 837225 + 1024144 = 915^2 + 1012^2 .

It is a cyclic number.

It is not a de Polignac number, because 1861369 - 2⁵ = 1861337 is a prime.

It is a super-2 number, since 2×1861369² = 6929389108322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2284 + ... + 2989.

It is an arithmetic number, because the mean of its divisors is an integer number (466749).

2^1861369 is an apocalyptic number.

It is an amenable number.

1861369 is a deficient number, since it is larger than the sum of its proper divisors (5627).

1861369 is an equidigital number, since it uses as much as digits as its factorization.

1861369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5626.

The product of its digits is 7776, while the sum is 34.

The square root of 1861369 is about 1364.3199771315. The cubic root of 1861369 is about 123.0110594414.

The spelling of 1861369 in words is "one million, eight hundred sixty-one thousand, three hundred sixty-nine".