28071481 has 2 divisors, whose sum is σ = 28071482. Its totient is φ = 28071480.

The previous prime is 28071479. The next prime is 28071487. The reversal of 28071481 is 18417082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19713600 + 8357881 = 4440^2 + 2891^2 .

It is a cyclic number.

It is not a de Polignac number, because 28071481 - 2¹ = 28071479 is a prime.

It is a super-2 number, since 2×28071481² = 1576016091066722, which contains 22 as substring.

Together with 28071479, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28071487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14035740 + 14035741.

It is an arithmetic number, because the mean of its divisors is an integer number (14035741).

Almost surely, 2^28071481 is an apocalyptic number.

It is an amenable number.

28071481 is a deficient number, since it is larger than the sum of its proper divisors (1).

28071481 is an equidigital number, since it uses as much as digits as its factorization.

28071481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 28071481 is about 5298.2526364831. The cubic root of 28071481 is about 303.9170804838.

The spelling of 28071481 in words is "twenty-eight million, seventy-one thousand, four hundred eighty-one".