28027638 has 12 divisors (see below), whose sum is σ = 60726588. Its totient is φ = 9342540.

The previous prime is 28027621. The next prime is 28027697. The reversal of 28027638 is 83672082.

It is a happy number.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 778528 + ... + 778563.

It is an arithmetic number, because the mean of its divisors is an integer number (5060549).

Almost surely, 2^28027638 is an apocalyptic number.

28027638 is an abundant number, since it is smaller than the sum of its proper divisors (32698950).

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

28027638 is a wasteful number, since it uses less digits than its factorization.

28027638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557099 (or 1557096 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 28027638 is about 5294.1135235278. The cubic root of 28027638 is about 303.7587753396.

It can be divided in two parts, 2802 and 7638, that added together give a triangular number (10440 = T₁₄₄).

The spelling of 28027638 in words is "twenty-eight million, twenty-seven thousand, six hundred thirty-eight".