31243123 has 2 divisors, whose sum is σ = 31243124. Its totient is φ = 31243122.

The previous prime is 31243111. The next prime is 31243139. The reversal of 31243123 is 32134213.

It is a weak prime.

It is an emirp because it is prime and its reverse (32134213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31243123 - 2¹⁷ = 31112051 is a prime.

It is a super-2 number, since 2×31243123² = 1952265469586258, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31243123.

It is not a weakly prime, because it can be changed into another prime (31243193) 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, 15621561 + 15621562.

It is an arithmetic number, because the mean of its divisors is an integer number (15621562).

Almost surely, 2^31243123 is an apocalyptic number.

31243123 is a deficient number, since it is larger than the sum of its proper divisors (1).

31243123 is an equidigital number, since it uses as much as digits as its factorization.

31243123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 19.

The square root of 31243123 is about 5589.5548123263. The cubic root of 31243123 is about 314.9571555065.

Adding to 31243123 its reverse (32134213), we get a palindrome (63377336).

The spelling of 31243123 in words is "thirty-one million, two hundred forty-three thousand, one hundred twenty-three".