1990439 has 4 divisors (see below), whose sum is σ = 2171400. Its totient is φ = 1809480.

The previous prime is 1990433. The next prime is 1990441. The reversal of 1990439 is 9340991.

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

It is a cyclic number.

It is not a de Polignac number, because 1990439 - 2¹⁶ = 1924903 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1990399 and 1990408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990433) 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, 90464 + ... + 90485.

It is an arithmetic number, because the mean of its divisors is an integer number (542850).

2^1990439 is an apocalyptic number.

1990439 is a deficient number, since it is larger than the sum of its proper divisors (180961).

1990439 is a wasteful number, since it uses less digits than its factorization.

1990439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180960.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 1990439 is about 1410.8291888106. The cubic root of 1990439 is about 125.7910157933.

The spelling of 1990439 in words is "one million, nine hundred ninety thousand, four hundred thirty-nine".