1990123 has 2 divisors, whose sum is σ = 1990124. Its totient is φ = 1990122.

The previous prime is 1990111. The next prime is 1990133. The reversal of 1990123 is 3210991.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1990123 is a prime.

1990123 is a lucky number.

It is equal to p₁₄₈₂₂₈ and since 1990123 and 148228 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (1990103) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995061 + 995062.

It is an arithmetic number, because the mean of its divisors is an integer number (995062).

2^1990123 is an apocalyptic number.

1990123 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990123 is an equidigital number, since it uses as much as digits as its factorization.

1990123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 25.

The square root of 1990123 is about 1410.7171934871. The cubic root of 1990123 is about 125.7843586246.

The spelling of 1990123 in words is "one million, nine hundred ninety thousand, one hundred twenty-three".