28912638 has 8 divisors (see below), whose sum is σ = 57825288. Its totient is φ = 9637544.

The previous prime is 28912621. The next prime is 28912643. The reversal of 28912638 is 83621982.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

28912638 is an admirable number.

It is a super-2 number, since 2×28912638² = 1671881272238088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28912596 and 28912605.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2409381 + ... + 2409392.

It is an arithmetic number, because the mean of its divisors is an integer number (7228161).

Almost surely, 2^28912638 is an apocalyptic number.

28912638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28912638 is a wasteful number, since it uses less digits than its factorization.

28912638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4818778.

The product of its digits is 41472, while the sum is 39.

The square root of 28912638 is about 5377.0473310173. The cubic root of 28912638 is about 306.9228622065.

The spelling of 28912638 in words is "twenty-eight million, nine hundred twelve thousand, six hundred thirty-eight".