28405069 has 32 divisors (see below), whose sum is σ = 37914624. Its totient is φ = 20623680.

The previous prime is 28405051. The next prime is 28405093. The reversal of 28405069 is 96050482.

It is a happy number.

It is not a de Polignac number, because 28405069 - 2⁵ = 28405037 is a prime.

It is a super-2 number, since 2×28405069² = 1613695889789522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28405099) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 75967 + ... + 76339.

It is an arithmetic number, because the mean of its divisors is an integer number (1184832).

Almost surely, 2^28405069 is an apocalyptic number.

It is an amenable number.

28405069 is a deficient number, since it is larger than the sum of its proper divisors (9509555).

28405069 is a wasteful number, since it uses less digits than its factorization.

28405069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 28405069 is about 5329.6406070203. The cubic root of 28405069 is about 305.1162112024.

The spelling of 28405069 in words is "twenty-eight million, four hundred five thousand, sixty-nine".