31121211231223 has 4 divisors (see below), whose sum is σ = 31134854903488. Its totient is φ = 31107567558960.

The previous prime is 31121211231217. The next prime is 31121211231239. The reversal of 31121211231223 is 32213211212113.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31121211231223 - 2²⁹ = 31120674360311 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31121211231203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6821832711 + ... + 6821837272.

It is an arithmetic number, because the mean of its divisors is an integer number (7783713725872).

Almost surely, 2^{31121211231223} is an apocalyptic number.

31121211231223 is a deficient number, since it is larger than the sum of its proper divisors (13643672265).

31121211231223 is a wasteful number, since it uses less digits than its factorization.

31121211231223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13643672264.

The product of its digits is 864, while the sum is 25.

Adding to 31121211231223 its reverse (32213211212113), we get a palindrome (63334422443336).

The spelling of 31121211231223 in words is "thirty-one trillion, one hundred twenty-one billion, two hundred eleven million, two hundred thirty-one thousand, two hundred twenty-three".