28438531 has 16 divisors (see below), whose sum is σ = 32659200. Its totient is φ = 24522400.

The previous prime is 28438517. The next prime is 28438541. The reversal of 28438531 is 13583482.

It is a happy number.

It is not a de Polignac number, because 28438531 - 2⁹ = 28438019 is a prime.

It is a super-2 number, since 2×28438531² = 1617500090875922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28438541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18066 + ... + 19576.

It is an arithmetic number, because the mean of its divisors is an integer number (2041200).

Almost surely, 2^28438531 is an apocalyptic number.

28438531 is a deficient number, since it is larger than the sum of its proper divisors (4220669).

28438531 is a wasteful number, since it uses less digits than its factorization.

28438531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1610.

The product of its digits is 23040, while the sum is 34.

The square root of 28438531 is about 5332.7789191002. The cubic root of 28438531 is about 305.2359761187.

The spelling of 28438531 in words is "twenty-eight million, four hundred thirty-eight thousand, five hundred thirty-one".