28408428 has 48 divisors (see below), whose sum is σ = 77988960. Its totient is φ = 8911872.

The previous prime is 28408421. The next prime is 28408433. The reversal of 28408428 is 82480482.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28408392 and 28408401.

It is not an unprimeable number, because it can be changed into a prime (28408421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5901 + ... + 9572.

It is an arithmetic number, because the mean of its divisors is an integer number (1624770).

Almost surely, 2^28408428 is an apocalyptic number.

It is an amenable number.

28408428 is an abundant number, since it is smaller than the sum of its proper divisors (49580532).

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

28408428 is a wasteful number, since it uses less digits than its factorization.

28408428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15503 (or 15495 counting only the distinct ones).

The product of its (nonzero) digits is 32768, while the sum is 36.

The square root of 28408428 is about 5329.9557221425. The cubic root of 28408428 is about 305.1282377525.

The spelling of 28408428 in words is "twenty-eight million, four hundred eight thousand, four hundred twenty-eight".