28990290 has 64 divisors (see below), whose sum is σ = 80216064. Its totient is φ = 6568128.

The previous prime is 28990289. The next prime is 28990307. The reversal of 28990290 is 9209982.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26127 + ... + 27213.

It is an arithmetic number, because the mean of its divisors is an integer number (1253376).

Almost surely, 2^28990290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28990290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40108032).

28990290 is an abundant number, since it is smaller than the sum of its proper divisors (51225774).

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

28990290 is a wasteful number, since it uses less digits than its factorization.

28990290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1231.

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 28990290 is about 5384.2631807890. The cubic root of 28990290 is about 307.1973888599.

The spelling of 28990290 in words is "twenty-eight million, nine hundred ninety thousand, two hundred ninety".