28170990 has 48 divisors (see below), whose sum is σ = 75963888. Its totient is φ = 7511616.

The previous prime is 28170979. The next prime is 28170997. The reversal of 28170990 is 9907182.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28170997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3367 + ... + 8226.

It is an arithmetic number, because the mean of its divisors is an integer number (1582581).

Almost surely, 2^28170990 is an apocalyptic number.

28170990 is an abundant number, since it is smaller than the sum of its proper divisors (47792898).

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

28170990 is a wasteful number, since it uses less digits than its factorization.

28170990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11615 (or 11603 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 28170990 is about 5307.6350665810. The cubic root of 28170990 is about 304.2757697886.

The spelling of 28170990 in words is "twenty-eight million, one hundred seventy thousand, nine hundred ninety".