28639386 has 16 divisors (see below), whose sum is σ = 63643200. Its totient is φ = 9546444.

The previous prime is 28639363. The next prime is 28639411. The reversal of 28639386 is 68393682.

28639386 is a `hidden beast` number, since 2 + 8 + 639 + 3 + 8 + 6 = 666.

It is a super-3 number, since 3×28639386³ (a number of 23 digits) contains 333 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 265126 + ... + 265233.

It is an arithmetic number, because the mean of its divisors is an integer number (3977700).

Almost surely, 2^28639386 is an apocalyptic number.

28639386 is an abundant number, since it is smaller than the sum of its proper divisors (35003814).

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

28639386 is a wasteful number, since it uses less digits than its factorization.

28639386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530370 (or 530364 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 28639386 is about 5351.5778981530. The cubic root of 28639386 is about 305.9528954790.

The spelling of 28639386 in words is "twenty-eight million, six hundred thirty-nine thousand, three hundred eighty-six".