133031221 has 2 divisors, whose sum is σ = 133031222. Its totient is φ = 133031220.

The previous prime is 133031203. The next prime is 133031257. The reversal of 133031221 is 122130331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68807025 + 64224196 = 8295^2 + 8014^2 .

It is a cyclic number.

It is not a de Polignac number, because 133031221 - 2¹¹ = 133029173 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 133031195 and 133031204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (133031621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66515610 + 66515611.

It is an arithmetic number, because the mean of its divisors is an integer number (66515611).

Almost surely, 2^133031221 is an apocalyptic number.

It is an amenable number.

133031221 is a deficient number, since it is larger than the sum of its proper divisors (1).

133031221 is an equidigital number, since it uses as much as digits as its factorization.

133031221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 133031221 is about 11533.9161172604. The cubic root of 133031221 is about 510.4868105835.

Adding to 133031221 its reverse (122130331), we get a palindrome (255161552).

The spelling of 133031221 in words is "one hundred thirty-three million, thirty-one thousand, two hundred twenty-one".