28638312 has 64 divisors (see below), whose sum is σ = 77328000. Its totient is φ = 8811264.

The previous prime is 28638307. The next prime is 28638317. The reversal of 28638312 is 21383682.

It is an interprime number because it is at equal distance from previous prime (28638307) and next prime (28638317).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (28638317) 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, 15114 + ... + 16902.

It is an arithmetic number, because the mean of its divisors is an integer number (1208250).

Almost surely, 2^28638312 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 28638312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38664000).

28638312 is an abundant number, since it is smaller than the sum of its proper divisors (48689688).

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

28638312 is a wasteful number, since it uses less digits than its factorization.

28638312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1850 (or 1846 counting only the distinct ones).

The product of its digits is 13824, while the sum is 33.

The square root of 28638312 is about 5351.4775529754. The cubic root of 28638312 is about 305.9490709380.

It can be divided in two parts, 2863 and 8312, that added together give a triangular number (11175 = T₁₄₉).

The spelling of 28638312 in words is "twenty-eight million, six hundred thirty-eight thousand, three hundred twelve".