1861149 has 4 divisors (see below), whose sum is σ = 2481536. Its totient is φ = 1240764.

The previous prime is 1861141. The next prime is 1861151. The reversal of 1861149 is 9411681.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1861149 - 2³ = 1861141 is a prime.

It is a D-number.

It is a Duffinian number.

1861149 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861141) 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, 310189 + ... + 310194.

It is an arithmetic number, because the mean of its divisors is an integer number (620384).

2^1861149 is an apocalyptic number.

It is an amenable number.

1861149 is a deficient number, since it is larger than the sum of its proper divisors (620387).

1861149 is an equidigital number, since it uses as much as digits as its factorization.

1861149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620386.

The product of its digits is 1728, while the sum is 30.

The square root of 1861149 is about 1364.2393485016. The cubic root of 1861149 is about 123.0062129190.

The spelling of 1861149 in words is "one million, eight hundred sixty-one thousand, one hundred forty-nine".