31201221121321 has 4 divisors (see below), whose sum is σ = 33036587069652. Its totient is φ = 29365855172992.

The previous prime is 31201221121307. The next prime is 31201221121327. The reversal of 31201221121321 is 12312112210213.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 28018336765225 + 3182884356096 = 5293235^2 + 1784064^2 .

It is a cyclic number.

It is not a de Polignac number, because 31201221121321 - 2⁵ = 31201221121289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31201221121292 and 31201221121301.

It is not an unprimeable number, because it can be changed into a prime (31201221121327) 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, 917682974140 + ... + 917682974173.

It is an arithmetic number, because the mean of its divisors is an integer number (8259146767413).

Almost surely, 2^{31201221121321} is an apocalyptic number.

It is an amenable number.

31201221121321 is a deficient number, since it is larger than the sum of its proper divisors (1835365948331).

31201221121321 is a wasteful number, since it uses less digits than its factorization.

31201221121321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1835365948330.

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 31201221121321 its reverse (12312112210213), we get a palindrome (43513333331534).

The spelling of 31201221121321 in words is "thirty-one trillion, two hundred one billion, two hundred twenty-one million, one hundred twenty-one thousand, three hundred twenty-one".