31633006721 has 2 divisors, whose sum is σ = 31633006722. Its totient is φ = 31633006720.

The previous prime is 31633006679. The next prime is 31633006723. The reversal of 31633006721 is 12760033613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20277760000 + 11355246721 = 142400^2 + 106561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31633006721 is a prime.

It is a super-2 number, since 2×31633006721² (a number of 22 digits) contains 22 as substring.

Together with 31633006723, 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 (31633006723) 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, 15816503360 + 15816503361.

It is an arithmetic number, because the mean of its divisors is an integer number (15816503361).

Almost surely, 2^31633006721 is an apocalyptic number.

It is an amenable number.

31633006721 is a deficient number, since it is larger than the sum of its proper divisors (1).

31633006721 is an equidigital number, since it uses as much as digits as its factorization.

31633006721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 32.

The spelling of 31633006721 in words is "thirty-one billion, six hundred thirty-three million, six thousand, seven hundred twenty-one".