28142500 has 30 divisors (see below), whose sum is σ = 61547486. Its totient is φ = 11256000.

The previous prime is 28142467. The next prime is 28142503. The reversal of 28142500 is 524182.

It can be written as a sum of positive squares in 5 ways, for example, as 6071296 + 22071204 = 2464^2 + 4698^2 .

It is not an unprimeable number, because it can be changed into a prime (28142503) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3129 + ... + 8128.

Almost surely, 2^28142500 is an apocalyptic number.

28142500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28142500 is an abundant number, since it is smaller than the sum of its proper divisors (33404986).

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

28142500 is a wasteful number, since it uses less digits than its factorization.

28142500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11281 (or 11264 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 28142500 is about 5304.9505181481. The cubic root of 28142500 is about 304.1731613884.

Adding to 28142500 its reverse (524182), we get a palindrome (28666682).

The spelling of 28142500 in words is "twenty-eight million, one hundred forty-two thousand, five hundred".