28171902 has 32 divisors (see below), whose sum is σ = 61968384. Its totient is φ = 8467200.

The previous prime is 28171883. The next prime is 28171903. The reversal of 28171902 is 20917182.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 28171902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28171903) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6702 + ... + 10062.

It is an arithmetic number, because the mean of its divisors is an integer number (1936512).

Almost surely, 2^28171902 is an apocalyptic number.

28171902 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 28171902, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30984192).

28171902 is an abundant number, since it is smaller than the sum of its proper divisors (33796482).

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

28171902 is a wasteful number, since it uses less digits than its factorization.

28171902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3504.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 28171902 is about 5307.7209798557. The cubic root of 28171902 is about 304.2790532670.

The spelling of 28171902 in words is "twenty-eight million, one hundred seventy-one thousand, nine hundred two".