31000111109909 has 2 divisors, whose sum is σ = 31000111109910. Its totient is φ = 31000111109908.

The previous prime is 31000111109899. The next prime is 31000111109971. The reversal of 31000111109909 is 90990111100013.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30492815320900 + 507295789009 = 5522030^2 + 712247^2 .

It is a cyclic number.

It is not a de Polignac number, because 31000111109909 - 2¹² = 31000111105813 is a prime.

It is a super-2 number, since 2×31000111109909² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31000111109309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15500055554954 + 15500055554955.

It is an arithmetic number, because the mean of its divisors is an integer number (15500055554955).

Almost surely, 2^{31000111109909} is an apocalyptic number.

It is an amenable number.

31000111109909 is a deficient number, since it is larger than the sum of its proper divisors (1).

31000111109909 is an equidigital number, since it uses as much as digits as its factorization.

31000111109909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2187, while the sum is 35.

The spelling of 31000111109909 in words is "thirty-one trillion, one hundred eleven million, one hundred nine thousand, nine hundred nine".