28157238 has 24 divisors (see below), whose sum is σ = 62976576. Its totient is φ = 9082800.

The previous prime is 28157191. The next prime is 28157249. The reversal of 28157238 is 83275182.

28157238 is a `hidden beast` number, since 2 + 81 + 572 + 3 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24673 + ... + 25788.

It is an arithmetic number, because the mean of its divisors is an integer number (2624024).

Almost surely, 2^28157238 is an apocalyptic number.

28157238 is an abundant number, since it is smaller than the sum of its proper divisors (34819338).

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

28157238 is a wasteful number, since it uses less digits than its factorization.

28157238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50500 (or 50497 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 28157238 is about 5306.3394162077. The cubic root of 28157238 is about 304.2262497983.

The spelling of 28157238 in words is "twenty-eight million, one hundred fifty-seven thousand, two hundred thirty-eight".