31712173 has 2 divisors, whose sum is σ = 31712174. Its totient is φ = 31712172.

The previous prime is 31712171. The next prime is 31712201. The reversal of 31712173 is 37121713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25270729 + 6441444 = 5027^2 + 2538^2 .

It is a cyclic number.

It is not a de Polignac number, because 31712173 - 2¹ = 31712171 is a prime.

Together with 31712171, 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 (31712171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15856086 + 15856087.

It is an arithmetic number, because the mean of its divisors is an integer number (15856087).

Almost surely, 2^31712173 is an apocalyptic number.

It is an amenable number.

31712173 is a deficient number, since it is larger than the sum of its proper divisors (1).

31712173 is an equidigital number, since it uses as much as digits as its factorization.

31712173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 882, while the sum is 25.

The square root of 31712173 is about 5631.3562309625. The cubic root of 31712173 is about 316.5254736511.

Adding to 31712173 its reverse (37121713), we get a palindrome (68833886).

The spelling of 31712173 in words is "thirty-one million, seven hundred twelve thousand, one hundred seventy-three".