28392540 has 48 divisors (see below), whose sum is σ = 86728320. Its totient is φ = 6882880.

The previous prime is 28392509. The next prime is 28392563. The reversal of 28392540 is 4529382.

It is a happy number.

It is a super-2 number, since 2×28392540² = 1612272655303200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20850 + ... + 22169.

It is an arithmetic number, because the mean of its divisors is an integer number (1806840).

Almost surely, 2^28392540 is an apocalyptic number.

28392540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28392540 is an abundant number, since it is smaller than the sum of its proper divisors (58335780).

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

28392540 is a wasteful number, since it uses less digits than its factorization.

28392540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43042 (or 43040 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 28392540 is about 5328.4650697926. The cubic root of 28392540 is about 305.0713440556.

The spelling of 28392540 in words is "twenty-eight million, three hundred ninety-two thousand, five hundred forty".