28665131 has 8 divisors (see below), whose sum is σ = 31309824. Its totient is φ = 26026920.

The previous prime is 28665101. The next prime is 28665139. The reversal of 28665131 is 13156682.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28665131 - 2¹⁴ = 28648747 is a prime.

It is a super-2 number, since 2×28665131² = 1643379470494322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28665139) 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, 16406 + ... + 18068.

It is an arithmetic number, because the mean of its divisors is an integer number (3913728).

Almost surely, 2^28665131 is an apocalyptic number.

28665131 is a deficient number, since it is larger than the sum of its proper divisors (2644693).

28665131 is a wasteful number, since it uses less digits than its factorization.

28665131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3241.

The product of its digits is 8640, while the sum is 32.

The square root of 28665131 is about 5353.9827231697. The cubic root of 28665131 is about 306.0445454680.

It can be divided in two parts, 286651 and 31, that added together give a palindrome (286682).

The spelling of 28665131 in words is "twenty-eight million, six hundred sixty-five thousand, one hundred thirty-one".