31221212133 has 16 divisors (see below), whose sum is σ = 42385608000. Its totient is φ = 20436341760.

The previous prime is 31221212107. The next prime is 31221212171. The reversal of 31221212133 is 33121212213.

It is not a de Polignac number, because 31221212133 - 2²⁹ = 30684341221 is a prime.

It is a super-3 number, since 3×31221212133³ (a number of 32 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31221212173) 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, 37893 + ... + 252741.

It is an arithmetic number, because the mean of its divisors is an integer number (2649100500).

Almost surely, 2^31221212133 is an apocalyptic number.

It is an amenable number.

31221212133 is a deficient number, since it is larger than the sum of its proper divisors (11164395867).

31221212133 is a wasteful number, since it uses less digits than its factorization.

31221212133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215732.

The product of its digits is 432, while the sum is 21.

Adding to 31221212133 its reverse (33121212213), we get a palindrome (64342424346).

The spelling of 31221212133 in words is "thirty-one billion, two hundred twenty-one million, two hundred twelve thousand, one hundred thirty-three".