28158280 has 16 divisors (see below), whose sum is σ = 63356220. Its totient is φ = 11263296.

The previous prime is 28158269. The next prime is 28158287. The reversal of 28158280 is 8285182.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 25462116 + 2696164 = 5046^2 + 1642^2 .

It is not an unprimeable number, because it can be changed into a prime (28158287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351939 + ... + 352018.

Almost surely, 2^28158280 is an apocalyptic number.

28158280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28158280 is an abundant number, since it is smaller than the sum of its proper divisors (35197940).

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

28158280 is a wasteful number, since it uses less digits than its factorization.

28158280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703968 (or 703964 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 34.

The square root of 28158280 is about 5306.4375997462. The cubic root of 28158280 is about 304.2300025319.

The spelling of 28158280 in words is "twenty-eight million, one hundred fifty-eight thousand, two hundred eighty".