28534431 has 4 divisors (see below), whose sum is σ = 38045912. Its totient is φ = 19022952.

The previous prime is 28534423. The next prime is 28534501. The reversal of 28534431 is 13443582.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 28534431 - 2³ = 28534423 is a prime.

It is a super-2 number, since 2×28534431² = 1628427504987522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28534931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4755736 + ... + 4755741.

It is an arithmetic number, because the mean of its divisors is an integer number (9511478).

Almost surely, 2^28534431 is an apocalyptic number.

28534431 is a deficient number, since it is larger than the sum of its proper divisors (9511481).

28534431 is an equidigital number, since it uses as much as digits as its factorization.

28534431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9511480.

The product of its digits is 11520, while the sum is 30.

The square root of 28534431 is about 5341.7629112494. The cubic root of 28534431 is about 305.5786952736.

It can be divided in two parts, 285 and 34431, that added together give a triangular number (34716 = T₂₆₃).

The spelling of 28534431 in words is "twenty-eight million, five hundred thirty-four thousand, four hundred thirty-one".