1990606 has 4 divisors (see below), whose sum is σ = 2985912. Its totient is φ = 995302.

The previous prime is 1990579. The next prime is 1990607. The reversal of 1990606 is 6060991.

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

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 497650 + ... + 497653.

It is an arithmetic number, because the mean of its divisors is an integer number (746478).

2^1990606 is an apocalyptic number.

1990606 is a deficient number, since it is larger than the sum of its proper divisors (995306).

1990606 is an equidigital number, since it uses as much as digits as its factorization.

1990606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 995305.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 1990606 is about 1410.8883726220. Note that the first 3 decimals coincide. The cubic root of 1990606 is about 125.7945336960.

The spelling of 1990606 in words is "one million, nine hundred ninety thousand, six hundred six".