133121213 has 4 divisors (see below), whose sum is σ = 135632988. Its totient is φ = 130609440.

The previous prime is 133121189. The next prime is 133121257. The reversal of 133121213 is 312121331.

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 47706649 + 85414564 = 6907^2 + 9242^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133121213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133121191 and 133121200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133123213) 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, 1255808 + ... + 1255913.

It is an arithmetic number, because the mean of its divisors is an integer number (33908247).

Almost surely, 2^133121213 is an apocalyptic number.

It is an amenable number.

133121213 is a deficient number, since it is larger than the sum of its proper divisors (2511775).

133121213 is an equidigital number, since it uses as much as digits as its factorization.

133121213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2511774.

The product of its digits is 108, while the sum is 17.

The square root of 133121213 is about 11537.8166478758. The cubic root of 133121213 is about 510.6018947810.

Adding to 133121213 its reverse (312121331), we get a palindrome (445242544).

The spelling of 133121213 in words is "one hundred thirty-three million, one hundred twenty-one thousand, two hundred thirteen".