990221312 has 44 divisors (see below), whose sum is σ = 1989290976. Its totient is φ = 492656640.

The previous prime is 990221303. The next prime is 990221317. The reversal of 990221312 is 213122099.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990221317) 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, 213773 + ... + 218355.

Almost surely, 2^990221312 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 990221312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (994645488).

990221312 is an abundant number, since it is smaller than the sum of its proper divisors (999069664).

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

990221312 is a wasteful number, since it uses less digits than its factorization.

990221312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4814 (or 4796 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 990221312 is about 31467.7821271217. The cubic root of 990221312 is about 996.7297544855.

The spelling of 990221312 in words is "nine hundred ninety million, two hundred twenty-one thousand, three hundred twelve".