28424440 has 32 divisors (see below), whose sum is σ = 69770160. Its totient is φ = 10336000.

The previous prime is 28424401. The next prime is 28424441. The reversal of 28424440 is 4442482.

It is a junction number, because it is equal to n+sod(n) for n = 28424399 and 28424408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28424441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31861 + ... + 32740.

Almost surely, 2^28424440 is an apocalyptic number.

28424440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28424440 is an abundant number, since it is smaller than the sum of its proper divisors (41345720).

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

28424440 is a wasteful number, since it uses less digits than its factorization.

28424440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64623 (or 64619 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 28.

The square root of 28424440 is about 5331.4575868143. The cubic root of 28424440 is about 305.1855540263.

The spelling of 28424440 in words is "twenty-eight million, four hundred twenty-four thousand, four hundred forty".