31123222233221 has 4 divisors (see below), whose sum is σ = 31332102919500. Its totient is φ = 30914341546944.

The previous prime is 31123222233203. The next prime is 31123222233239. The reversal of 31123222233221 is 12233222232113.

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

It is an interprime number because it is at equal distance from previous prime (31123222233203) and next prime (31123222233239).

It can be written as a sum of positive squares in 2 ways, for example, as 20420909102500 + 10702313130721 = 4518950^2 + 3271439^2 .

It is a cyclic number.

It is not a de Polignac number, because 31123222233221 - 2⁴² = 26725175722117 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 (31123222233241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104440342916 + ... + 104440343213.

It is an arithmetic number, because the mean of its divisors is an integer number (7833025729875).

Almost surely, 2^{31123222233221} is an apocalyptic number.

It is an amenable number.

31123222233221 is a deficient number, since it is larger than the sum of its proper divisors (208880686279).

31123222233221 is a wasteful number, since it uses less digits than its factorization.

31123222233221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208880686278.

The product of its digits is 10368, while the sum is 29.

Adding to 31123222233221 its reverse (12233222232113), we get a palindrome (43356444465334).

The spelling of 31123222233221 in words is "thirty-one trillion, one hundred twenty-three billion, two hundred twenty-two million, two hundred thirty-three thousand, two hundred twenty-one".