990420 has 48 divisors (see below), whose sum is σ = 2939328. Its totient is φ = 248320.

The previous prime is 990397. The next prime is 990463. The reversal of 990420 is 24099.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 535 + ... + 1505.

It is an arithmetic number, because the mean of its divisors is an integer number (61236).

2⁹⁹⁰⁴²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 990420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1469664).

990420 is an abundant number, since it is smaller than the sum of its proper divisors (1948908).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

990420 is a wasteful number, since it uses less digits than its factorization.

990420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000 (or 998 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 990420 is about 995.1984726676. The cubic root of 990420 is about 99.6796414667.

The spelling of 990420 in words is "nine hundred ninety thousand, four hundred twenty".