28047431 has 2 divisors, whose sum is σ = 28047432. Its totient is φ = 28047430.

The previous prime is 28047421. The next prime is 28047451. The reversal of 28047431 is 13474082.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28047431 is a prime.

It is a super-2 number, since 2×28047431² = 1573316771399522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28047394 and 28047403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28047421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14023715 + 14023716.

It is an arithmetic number, because the mean of its divisors is an integer number (14023716).

Almost surely, 2^28047431 is an apocalyptic number.

28047431 is a deficient number, since it is larger than the sum of its proper divisors (1).

28047431 is an equidigital number, since it uses as much as digits as its factorization.

28047431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 28047431 is about 5295.9825339591. The cubic root of 28047431 is about 303.8302629038.

The spelling of 28047431 in words is "twenty-eight million, forty-seven thousand, four hundred thirty-one".