31123123 has 2 divisors, whose sum is σ = 31123124. Its totient is φ = 31123122.

The previous prime is 31123109. The next prime is 31123139. The reversal of 31123123 is 32132113.

It is an a-pointer prime, because the next prime (31123139) can be obtained adding 31123123 to its sum of digits (16).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31123123 - 2¹³ = 31114931 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31123097 and 31123106.

It is not a weakly prime, because it can be changed into another prime (31123193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15561561 + 15561562.

It is an arithmetic number, because the mean of its divisors is an integer number (15561562).

Almost surely, 2^31123123 is an apocalyptic number.

31123123 is a deficient number, since it is larger than the sum of its proper divisors (1).

31123123 is an equidigital number, since it uses as much as digits as its factorization.

31123123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108, while the sum is 16.

The square root of 31123123 is about 5578.8101778067. The cubic root of 31123123 is about 314.5534042528.

Adding to 31123123 its reverse (32132113), we get a palindrome (63255236).

The spelling of 31123123 in words is "thirty-one million, one hundred twenty-three thousand, one hundred twenty-three".