28405930 has 16 divisors (see below), whose sum is σ = 58435200. Its totient is φ = 9739152.

The previous prime is 28405913. The next prime is 28405939. The reversal of 28405930 is 3950482.

It is a junction number, because it is equal to n+sod(n) for n = 28405892 and 28405901.

It is not an unprimeable number, because it can be changed into a prime (28405939) 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, 202830 + ... + 202969.

It is an arithmetic number, because the mean of its divisors is an integer number (3652200).

Almost surely, 2^28405930 is an apocalyptic number.

28405930 is an abundant number, since it is smaller than the sum of its proper divisors (30029270).

28405930 is a wasteful number, since it uses less digits than its factorization.

28405930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405813.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 28405930 is about 5329.7213810855. The cubic root of 28405930 is about 305.1192940137.

It can be divided in two parts, 284059 and 30, that added together give a square (284089 = 533²).

The spelling of 28405930 in words is "twenty-eight million, four hundred five thousand, nine hundred thirty".