31638029 has 2 divisors, whose sum is σ = 31638030. Its totient is φ = 31638028.

The previous prime is 31638007. The next prime is 31638031. The reversal of 31638029 is 92083613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25502500 + 6135529 = 5050^2 + 2477^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31638029 is a prime.

Together with 31638031, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 31637986 and 31638004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31638049) 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, 15819014 + 15819015.

It is an arithmetic number, because the mean of its divisors is an integer number (15819015).

Almost surely, 2^31638029 is an apocalyptic number.

It is an amenable number.

31638029 is a deficient number, since it is larger than the sum of its proper divisors (1).

31638029 is an equidigital number, since it uses as much as digits as its factorization.

31638029 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 31638029 is about 5624.7692397111. The cubic root of 31638029 is about 316.2785991728.

The spelling of 31638029 in words is "thirty-one million, six hundred thirty-eight thousand, twenty-nine".