33213131221 has 8 divisors (see below), whose sum is σ = 33763743000. Its totient is φ = 32662717440.

The previous prime is 33213131197. The next prime is 33213131239. The reversal of 33213131221 is 12213131233.

It can be written as a sum of positive squares in 4 ways, for example, as 4444222225 + 28768908996 = 66665^2 + 169614^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 33213131221 - 2²⁵ = 33179576789 is a prime.

It is a super-2 number, since 2×33213131221² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 33213131192 and 33213131201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33213131521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 310245 + ... + 403333.

It is an arithmetic number, because the mean of its divisors is an integer number (4220467875).

Almost surely, 2^33213131221 is an apocalyptic number.

It is an amenable number.

33213131221 is a deficient number, since it is larger than the sum of its proper divisors (550611779).

33213131221 is an equidigital number, since it uses as much as digits as its factorization.

33213131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98999.

The product of its digits is 648, while the sum is 22.

Adding to 33213131221 its reverse (12213131233), we get a palindrome (45426262454).

The spelling of 33213131221 in words is "thirty-three billion, two hundred thirteen million, one hundred thirty-one thousand, two hundred twenty-one".