9990450 has 54 divisors (see below), whose sum is σ = 27022359. Its totient is φ = 2646240.

The previous prime is 9990403. The next prime is 9990457. The reversal of 9990450 is 540999.

It can be written as a sum of positive squares in 5 ways, for example, as 423801 + 9566649 = 651^2 + 3093^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=2235.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (9990457) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 66976 + ... + 67124.

Almost surely, 2^9990450 is an apocalyptic number.

9990450 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 9990450

9990450 is an abundant number, since it is smaller than the sum of its proper divisors (17031909).

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

9990450 is a wasteful number, since it uses less digits than its factorization.

9990450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 14580, while the sum is 36.

The square root of 9990450 is about 3160.7673119039. The cubic root of 9990450 is about 215.3748643218.

It can be divided in two parts, 9990 and 450, that added together give a triangular number (10440 = T₁₄₄).

The spelling of 9990450 in words is "nine million, nine hundred ninety thousand, four hundred fifty".