1881905 has 8 divisors (see below), whose sum is σ = 2284200. Its totient is φ = 1488256.

The previous prime is 1881899. The next prime is 1881907. The reversal of 1881905 is 5091881.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 461041 + 1420864 = 679^2 + 1192^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1881905 - 2⁴ = 1881889 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1881907) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1670 + ... + 2559.

It is an arithmetic number, because the mean of its divisors is an integer number (285525).

2^1881905 is an apocalyptic number.

It is an amenable number.

1881905 is a deficient number, since it is larger than the sum of its proper divisors (402295).

1881905 is an equidigital number, since it uses as much as digits as its factorization.

1881905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4323.

The product of its (nonzero) digits is 2880, while the sum is 32.

The square root of 1881905 is about 1371.8254262114. The cubic root of 1881905 is about 123.4617888966.

The spelling of 1881905 in words is "one million, eight hundred eighty-one thousand, nine hundred five".