31091013649 has 2 divisors, whose sum is σ = 31091013650. Its totient is φ = 31091013648.

The previous prime is 31091013599. The next prime is 31091013697. The reversal of 31091013649 is 94631019013.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18125775424 + 12965238225 = 134632^2 + 113865^2 .

It is a cyclic number.

It is not a de Polignac number, because 31091013649 - 2⁹ = 31091013137 is a prime.

It is a super-2 number, since 2×31091013649² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31091013049) 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, 15545506824 + 15545506825.

It is an arithmetic number, because the mean of its divisors is an integer number (15545506825).

Almost surely, 2^31091013649 is an apocalyptic number.

It is an amenable number.

31091013649 is a deficient number, since it is larger than the sum of its proper divisors (1).

31091013649 is an equidigital number, since it uses as much as digits as its factorization.

31091013649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 37.

The spelling of 31091013649 in words is "thirty-one billion, ninety-one million, thirteen thousand, six hundred forty-nine".