28242405 has 16 divisors (see below), whose sum is σ = 50208960. Its totient is φ = 15062544.

The previous prime is 28242397. The next prime is 28242407. The reversal of 28242405 is 50424282.

It is a happy number.

It is not a de Polignac number, because 28242405 - 2³ = 28242397 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28242407) 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, 104467 + ... + 104736.

It is an arithmetic number, because the mean of its divisors is an integer number (3138060).

Almost surely, 2^28242405 is an apocalyptic number.

It is an amenable number.

28242405 is a deficient number, since it is larger than the sum of its proper divisors (21966555).

28242405 is a wasteful number, since it uses less digits than its factorization.

28242405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209217 (or 209211 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 27.

The square root of 28242405 is about 5314.3583808396. The cubic root of 28242405 is about 304.5326713955.

Adding to 28242405 its reverse (50424282), we get a palindrome (78666687).

The spelling of 28242405 in words is "twenty-eight million, two hundred forty-two thousand, four hundred five".