28140237 has 32 divisors (see below), whose sum is σ = 43747200. Its totient is φ = 17853696.

The previous prime is 28140199. The next prime is 28140269. The reversal of 28140237 is 73204182.

It is not a de Polignac number, because 28140237 - 2¹¹ = 28138189 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 28140237.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28140137) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 64773 + ... + 65205.

It is an arithmetic number, because the mean of its divisors is an integer number (1367100).

Almost surely, 2^28140237 is an apocalyptic number.

28140237 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

28140237 is a deficient number, since it is larger than the sum of its proper divisors (15606963).

28140237 is a wasteful number, since it uses less digits than its factorization.

28140237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554 (or 548 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 28140237 is about 5304.7372225210. The cubic root of 28140237 is about 304.1650080934.

The spelling of 28140237 in words is "twenty-eight million, one hundred forty thousand, two hundred thirty-seven".