31920841 has 2 divisors, whose sum is σ = 31920842. Its totient is φ = 31920840.

The previous prime is 31920839. The next prime is 31920859. The reversal of 31920841 is 14802913.

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., 17640000 + 14280841 = 4200^2 + 3779^2 .

It is a cyclic number.

It is not a de Polignac number, because 31920841 - 2¹ = 31920839 is a prime.

Together with 31920839, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31920821) 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, 15960420 + 15960421.

It is an arithmetic number, because the mean of its divisors is an integer number (15960421).

Almost surely, 2^31920841 is an apocalyptic number.

It is an amenable number.

31920841 is a deficient number, since it is larger than the sum of its proper divisors (1).

31920841 is an equidigital number, since it uses as much as digits as its factorization.

31920841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 31920841 is about 5649.8531839332. The cubic root of 31920841 is about 317.2182086521.

It can be divided in two parts, 31920 and 841, that added together give a square (32761 = 181²).

The spelling of 31920841 in words is "thirty-one million, nine hundred twenty thousand, eight hundred forty-one".