990623 has 4 divisors (see below), whose sum is σ = 1009368. Its totient is φ = 971880.

The previous prime is 990599. The next prime is 990631. The reversal of 990623 is 326099.

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 990623 - 2⁶ = 990559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990643) 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, 9293 + ... + 9398.

It is an arithmetic number, because the mean of its divisors is an integer number (252342).

2⁹⁹⁰⁶²³ is an apocalyptic number.

990623 is a deficient number, since it is larger than the sum of its proper divisors (18745).

990623 is a wasteful number, since it uses less digits than its factorization.

990623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18744.

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 990623 is about 995.3004571485. The cubic root of 990623 is about 99.6864512326.

The spelling of 990623 in words is "nine hundred ninety thousand, six hundred twenty-three".