31103993 has 2 divisors, whose sum is σ = 31103994. Its totient is φ = 31103992.

The previous prime is 31103957. The next prime is 31104049. The reversal of 31103993 is 39930113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19598329 + 11505664 = 4427^2 + 3392^2 .

It is a cyclic number.

It is not a de Polignac number, because 31103993 - 2⁶ = 31103929 is a prime.

It is equal to p_1921934 and since 31103993 and 1921934 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (31106993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15551996 + 15551997.

It is an arithmetic number, because the mean of its divisors is an integer number (15551997).

Almost surely, 2^31103993 is an apocalyptic number.

It is an amenable number.

31103993 is a deficient number, since it is larger than the sum of its proper divisors (1).

31103993 is an equidigital number, since it uses as much as digits as its factorization.

31103993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2187, while the sum is 29.

The square root of 31103993 is about 5577.0953909719. The cubic root of 31103993 is about 314.4889437130.

The spelling of 31103993 in words is "thirty-one million, one hundred three thousand, nine hundred ninety-three".