1819949 has 4 divisors (see below), whose sum is σ = 1864380. Its totient is φ = 1775520.

The previous prime is 1819933. The next prime is 1819957. The reversal of 1819949 is 9499181.

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 964324 + 855625 = 982^2 + 925^2 .

It is a cyclic number.

It is not a de Polignac number, because 1819949 - 2⁴ = 1819933 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41), and also a Moran number because the ratio is a prime number: 44389 = 1819949 / (1 + 8 + 1 + 9 + 9 + 4 + 9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1819999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22154 + ... + 22235.

It is an arithmetic number, because the mean of its divisors is an integer number (466095).

2^1819949 is an apocalyptic number.

It is an amenable number.

1819949 is a deficient number, since it is larger than the sum of its proper divisors (44431).

1819949 is an equidigital number, since it uses as much as digits as its factorization.

1819949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44430.

The product of its digits is 23328, while the sum is 41.

The square root of 1819949 is about 1349.0548543332. The cubic root of 1819949 is about 122.0917745357.

The spelling of 1819949 in words is "one million, eight hundred nineteen thousand, nine hundred forty-nine".