990023 has 2 divisors, whose sum is σ = 990024. Its totient is φ = 990022.

The previous prime is 990013. The next prime is 990037. The reversal of 990023 is 320099.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 990023 - 2⁶ = 989959 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (990013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495011 + 495012.

It is an arithmetic number, because the mean of its divisors is an integer number (495012).

2⁹⁹⁰⁰²³ is an apocalyptic number.

990023 is a deficient number, since it is larger than the sum of its proper divisors (1).

990023 is an equidigital number, since it uses as much as digits as its factorization.

990023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 486, while the sum is 23.

The square root of 990023 is about 994.9989949744. The cubic root of 990023 is about 99.6663211560. Note that the first 3 decimals are identical.

The spelling of 990023 in words is "nine hundred ninety thousand, twenty-three".