31323202221 has 16 divisors (see below), whose sum is σ = 42898381184. Its totient is φ = 20315219904.

The previous prime is 31323202213. The next prime is 31323202237. The reversal of 31323202221 is 12220232313.

It is a happy number.

It is not a de Polignac number, because 31323202221 - 2³ = 31323202213 is a prime.

It is a super-2 number, since 2×31323202221² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31323202201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1362000 + ... + 1384806.

It is an arithmetic number, because the mean of its divisors is an integer number (2681148824).

Almost surely, 2^31323202221 is an apocalyptic number.

It is an amenable number.

31323202221 is a deficient number, since it is larger than the sum of its proper divisors (11575178963).

31323202221 is a wasteful number, since it uses less digits than its factorization.

31323202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35220.

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 31323202221 its reverse (12220232313), we get a palindrome (43543434534).

The spelling of 31323202221 in words is "thirty-one billion, three hundred twenty-three million, two hundred two thousand, two hundred twenty-one".