28440630 has 48 divisors (see below), whose sum is σ = 75675600. Its totient is φ = 7406784.

The previous prime is 28440617. The next prime is 28440641. The reversal of 28440630 is 3604482.

28440630 is a `hidden beast` number, since 28 + 4 + 4 + 0 + 630 = 666.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28440594 and 28440603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 196 + ... + 7544.

It is an arithmetic number, because the mean of its divisors is an integer number (1576575).

Almost surely, 2^28440630 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28440630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37837800).

28440630 is an abundant number, since it is smaller than the sum of its proper divisors (47234970).

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

28440630 is a wasteful number, since it uses less digits than its factorization.

28440630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7405 (or 7402 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 28440630 is about 5332.9757171770. The cubic root of 28440630 is about 305.2434855848.

The spelling of 28440630 in words is "twenty-eight million, four hundred forty thousand, six hundred thirty".