133316921 has 2 divisors, whose sum is σ = 133316922. Its totient is φ = 133316920.

The previous prime is 133316891. The next prime is 133316923. The reversal of 133316921 is 129613331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114490000 + 18826921 = 10700^2 + 4339^2 .

It is a cyclic number.

It is not a de Polignac number, because 133316921 - 2¹⁴ = 133300537 is a prime.

Together with 133316923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (133316923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66658460 + 66658461.

It is an arithmetic number, because the mean of its divisors is an integer number (66658461).

Almost surely, 2^133316921 is an apocalyptic number.

It is an amenable number.

133316921 is a deficient number, since it is larger than the sum of its proper divisors (1).

133316921 is an equidigital number, since it uses as much as digits as its factorization.

133316921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2916, while the sum is 29.

The square root of 133316921 is about 11546.2946870414. The cubic root of 133316921 is about 510.8519925258.

The spelling of 133316921 in words is "one hundred thirty-three million, three hundred sixteen thousand, nine hundred twenty-one".