31123221202 has 4 divisors (see below), whose sum is σ = 46684831806. Its totient is φ = 15561610600.

The previous prime is 31123221193. The next prime is 31123221203. The reversal of 31123221202 is 20212232113.

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

It can be written as a sum of positive squares in only one way, i.e., 27549692361 + 3573528841 = 165981^2 + 59779^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 31123221202.

It is not an unprimeable number, because it can be changed into a prime (31123221203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7780805299 + ... + 7780805302.

Almost surely, 2^31123221202 is an apocalyptic number.

31123221202 is a deficient number, since it is larger than the sum of its proper divisors (15561610604).

31123221202 is a wasteful number, since it uses less digits than its factorization.

31123221202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15561610603.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 31123221202 its reverse (20212232113), we get a palindrome (51335453315).

The spelling of 31123221202 in words is "thirty-one billion, one hundred twenty-three million, two hundred twenty-one thousand, two hundred two".