290665728 has 216 divisors, whose sum is σ = 914023656. Its totient is φ = 88473600.

The previous prime is 290665709. The next prime is 290665741. The reversal of 290665728 is 827566092.

It can be written as a sum of positive squares in 4 ways, for example, as 1937664 + 288728064 = 1392^2 + 16992^2 .

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1605798 + ... + 1605978.

It is an arithmetic number, because the mean of its divisors is an integer number (4231591).

Almost surely, 2^290665728 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 290665728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (457011828).

290665728 is an abundant number, since it is smaller than the sum of its proper divisors (623357928).

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

290665728 is a wasteful number, since it uses less digits than its factorization.

290665728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 290665728 is about 17048.9216081252. The cubic root of 290665728 is about 662.4167047527.

The spelling of 290665728 in words is "two hundred ninety million, six hundred sixty-five thousand, seven hundred twenty-eight".