31213221322 has 4 divisors (see below), whose sum is σ = 46819831986. Its totient is φ = 15606610660.

The previous prime is 31213221307. The next prime is 31213221323. The reversal of 31213221322 is 22312231213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 22312231213 = 17 ⋅1312484189.

It can be written as a sum of positive squares in only one way, i.e., 16697549961 + 14515671361 = 129219^2 + 120481^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31213221293 and 31213221302.

It is not an unprimeable number, because it can be changed into a prime (31213221323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7803305329 + ... + 7803305332.

Almost surely, 2^31213221322 is an apocalyptic number.

31213221322 is a deficient number, since it is larger than the sum of its proper divisors (15606610664).

31213221322 is a wasteful number, since it uses less digits than its factorization.

31213221322 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15606610663.

The product of its digits is 864, while the sum is 22.

Adding to 31213221322 its reverse (22312231213), we get a palindrome (53525452535).

The spelling of 31213221322 in words is "thirty-one billion, two hundred thirteen million, two hundred twenty-one thousand, three hundred twenty-two".