28687838 has 8 divisors (see below), whose sum is σ = 43458120. Its totient is φ = 14201800.

The previous prime is 28687817. The next prime is 28687843. The reversal of 28687838 is 83878682.

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

It is a super-2 number, since 2×28687838² = 1645984098228488, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70808 + ... + 71211.

It is an arithmetic number, because the mean of its divisors is an integer number (5432265).

Almost surely, 2^28687838 is an apocalyptic number.

28687838 is a deficient number, since it is larger than the sum of its proper divisors (14770282).

28687838 is a wasteful number, since it uses less digits than its factorization.

28687838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142122.

The product of its digits is 1032192, while the sum is 50.

The square root of 28687838 is about 5356.1028742921. The cubic root of 28687838 is about 306.1253349044.

The spelling of 28687838 in words is "twenty-eight million, six hundred eighty-seven thousand, eight hundred thirty-eight".