28857138 has 16 divisors (see below), whose sum is σ = 57879360. Its totient is φ = 9591536.

The previous prime is 28857137. The next prime is 28857139. The reversal of 28857138 is 83175882.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28857137) and next prime (28857139).

It is a self number, because there is not a number n which added to its sum of digits gives 28857138.

It is not an unprimeable number, because it can be changed into a prime (28857131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4545 + ... + 8852.

It is an arithmetic number, because the mean of its divisors is an integer number (3617460).

Almost surely, 2^28857138 is an apocalyptic number.

28857138 is an abundant number, since it is smaller than the sum of its proper divisors (29022222).

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

28857138 is a wasteful number, since it uses less digits than its factorization.

28857138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13761.

The product of its digits is 107520, while the sum is 42.

The square root of 28857138 is about 5371.8840270430. The cubic root of 28857138 is about 306.7263491801.

The spelling of 28857138 in words is "twenty-eight million, eight hundred fifty-seven thousand, one hundred thirty-eight".