281687473 has 2 divisors, whose sum is σ = 281687474. Its totient is φ = 281687472.

The previous prime is 281687437. The next prime is 281687489. The reversal of 281687473 is 374786182.

Together with previous prime (281687437) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 266570929 + 15116544 = 16327^2 + 3888^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-281687473 is a prime.

It is a super-3 number, since 3×281687473³ (a number of 26 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (281681473) 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, 140843736 + 140843737.

It is an arithmetic number, because the mean of its divisors is an integer number (140843737).

Almost surely, 2^281687473 is an apocalyptic number.

It is an amenable number.

281687473 is a deficient number, since it is larger than the sum of its proper divisors (1).

281687473 is an equidigital number, since it uses as much as digits as its factorization.

281687473 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 451584, while the sum is 46.

The square root of 281687473 is about 16783.5476881379. The cubic root of 281687473 is about 655.5248773423.

The spelling of 281687473 in words is "two hundred eighty-one million, six hundred eighty-seven thousand, four hundred seventy-three".