31648789 has 2 divisors, whose sum is σ = 31648790. Its totient is φ = 31648788.

The previous prime is 31648787. The next prime is 31648807. The reversal of 31648789 is 98784613.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31248100 + 400689 = 5590^2 + 633^2 .

It is a cyclic number.

It is not a de Polignac number, because 31648789 - 2¹ = 31648787 is a prime.

Together with 31648787, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31648783) 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, 15824394 + 15824395.

It is an arithmetic number, because the mean of its divisors is an integer number (15824395).

Almost surely, 2^31648789 is an apocalyptic number.

It is an amenable number.

31648789 is a deficient number, since it is larger than the sum of its proper divisors (1).

31648789 is an equidigital number, since it uses as much as digits as its factorization.

31648789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 46.

The square root of 31648789 is about 5625.7256420839. The cubic root of 31648789 is about 316.3144502472.

The spelling of 31648789 in words is "thirty-one million, six hundred forty-eight thousand, seven hundred eighty-nine".