28137508 has 12 divisors (see below), whose sum is σ = 56275072. Its totient is φ = 12058920.

The previous prime is 28137503. The next prime is 28137539. The reversal of 28137508 is 80573182.

28137508 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (28137503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 502428 + ... + 502483.

Almost surely, 2^28137508 is an apocalyptic number.

28137508 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28137508 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

28137508 is a wasteful number, since it uses less digits than its factorization.

28137508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1004922 (or 1004920 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 28137508 is about 5304.4799933641. The cubic root of 28137508 is about 304.1551752795.

The spelling of 28137508 in words is "twenty-eight million, one hundred thirty-seven thousand, five hundred eight".