28038431 has 4 divisors (see below), whose sum is σ = 28567512. Its totient is φ = 27509352.

The previous prime is 28038421. The next prime is 28038499. The reversal of 28038431 is 13483082.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 28038431 - 2²² = 23844127 is a prime.

It is a super-2 number, since 2×28038431² = 1572307225883522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28038394 and 28038403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28038401) 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, 264461 + ... + 264566.

It is an arithmetic number, because the mean of its divisors is an integer number (7141878).

Almost surely, 2^28038431 is an apocalyptic number.

28038431 is a deficient number, since it is larger than the sum of its proper divisors (529081).

28038431 is an equidigital number, since it uses as much as digits as its factorization.

28038431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 529080.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 28038431 is about 5295.1327650966. The cubic root of 28038431 is about 303.7977612354.

The spelling of 28038431 in words is "twenty-eight million, thirty-eight thousand, four hundred thirty-one".