1881399 has 16 divisors (see below), whose sum is σ = 2844800. Its totient is φ = 1096416.

The previous prime is 1881391. The next prime is 1881401. The reversal of 1881399 is 9931881.

It is a happy number.

It is not a de Polignac number, because 1881399 - 2³ = 1881391 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

1881399 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1881391) 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 15 ways as a sum of consecutive naturals, for example, 529 + ... + 2010.

It is an arithmetic number, because the mean of its divisors is an integer number (177800).

2^1881399 is an apocalyptic number.

1881399 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1881399 is a deficient number, since it is larger than the sum of its proper divisors (963401).

1881399 is a wasteful number, since it uses less digits than its factorization.

1881399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2574.

The product of its digits is 15552, while the sum is 39.

The square root of 1881399 is about 1371.6409880140. The cubic root of 1881399 is about 123.4507225808.

The spelling of 1881399 in words is "one million, eight hundred eighty-one thousand, three hundred ninety-nine".