1861231 has 4 divisors (see below), whose sum is σ = 1870264. Its totient is φ = 1852200.

The previous prime is 1861219. The next prime is 1861253. The reversal of 1861231 is 1321681.

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

It is a 3-Lehmer number, since φ(1861231) divides (1861231-1)³.

It is a cyclic number.

It is not a de Polignac number, because 1861231 - 2⁷ = 1861103 is a prime.

It is a super-2 number, since 2×1861231² = 6928361670722, which contains 22 as substring.

It is a Duffinian number.

1861231 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861261) 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, 4200 + ... + 4621.

It is an arithmetic number, because the mean of its divisors is an integer number (467566).

2^1861231 is an apocalyptic number.

1861231 is a deficient number, since it is larger than the sum of its proper divisors (9033).

1861231 is an equidigital number, since it uses as much as digits as its factorization.

1861231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9032.

The product of its digits is 288, while the sum is 22.

The square root of 1861231 is about 1364.2694015479. The cubic root of 1861231 is about 123.0080193947.

The spelling of 1861231 in words is "one million, eight hundred sixty-one thousand, two hundred thirty-one".