28497728 has 28 divisors (see below), whose sum is σ = 64629792. Its totient is φ = 12213120.

The previous prime is 28497719. The next prime is 28497737. The reversal of 28497728 is 82779482.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28497719) and next prime (28497737).

It is a tau number, because it is divible by the number of its divisors (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31358 + ... + 32253.

Almost surely, 2^28497728 is an apocalyptic number.

28497728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28497728 is an abundant number, since it is smaller than the sum of its proper divisors (36132064).

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

28497728 is an equidigital number, since it uses as much as digits as its factorization.

28497728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63630 (or 63620 counting only the distinct ones).

The product of its digits is 451584, while the sum is 47.

The square root of 28497728 is about 5338.3263294782. The cubic root of 28497728 is about 305.4476200931.

The spelling of 28497728 in words is "twenty-eight million, four hundred ninety-seven thousand, seven hundred twenty-eight".