28155590 has 8 divisors (see below), whose sum is σ = 50680080. Its totient is φ = 11262232.

The previous prime is 28155581. The next prime is 28155593. The reversal of 28155590 is 9555182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 28155590.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28155593) 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, 1407770 + ... + 1407789.

It is an arithmetic number, because the mean of its divisors is an integer number (6335010).

Almost surely, 2^28155590 is an apocalyptic number.

28155590 is a deficient number, since it is larger than the sum of its proper divisors (22524490).

28155590 is a wasteful number, since it uses less digits than its factorization.

28155590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2815566.

The product of its (nonzero) digits is 18000, while the sum is 35.

The square root of 28155590 is about 5306.1841279775. The cubic root of 28155590 is about 304.2203143837.

The spelling of 28155590 in words is "twenty-eight million, one hundred fifty-five thousand, five hundred ninety".