133431311021 has 2 divisors, whose sum is σ = 133431311022. Its totient is φ = 133431311020.

The previous prime is 133431311011. The next prime is 133431311051. The reversal of 133431311021 is 120113134331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121525446025 + 11905864996 = 348605^2 + 109114^2 .

It is a cyclic number.

It is not a de Polignac number, because 133431311021 - 2²² = 133427116717 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (133431311011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66715655510 + 66715655511.

It is an arithmetic number, because the mean of its divisors is an integer number (66715655511).

Almost surely, 2^133431311021 is an apocalyptic number.

It is an amenable number.

133431311021 is a deficient number, since it is larger than the sum of its proper divisors (1).

133431311021 is an equidigital number, since it uses as much as digits as its factorization.

133431311021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 23.

Adding to 133431311021 its reverse (120113134331), we get a palindrome (253544445352).

The spelling of 133431311021 in words is "one hundred thirty-three billion, four hundred thirty-one million, three hundred eleven thousand, twenty-one".