31728679 has 2 divisors, whose sum is σ = 31728680. Its totient is φ = 31728678.

The previous prime is 31728649. The next prime is 31728769. The reversal of 31728679 is 97682713.

It is a happy number.

Together with next prime (31728769) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31728679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31728649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15864339 + 15864340.

It is an arithmetic number, because the mean of its divisors is an integer number (15864340).

Almost surely, 2^31728679 is an apocalyptic number.

31728679 is a deficient number, since it is larger than the sum of its proper divisors (1).

31728679 is an equidigital number, since it uses as much as digits as its factorization.

31728679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 127008, while the sum is 43.

The square root of 31728679 is about 5632.8215842506. The cubic root of 31728679 is about 316.5803806767.

The spelling of 31728679 in words is "thirty-one million, seven hundred twenty-eight thousand, six hundred seventy-nine".