133494837781 has 2 divisors, whose sum is σ = 133494837782. Its totient is φ = 133494837780.

The previous prime is 133494837779. The next prime is 133494837803. The reversal of 133494837781 is 187738494331.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69978237156 + 63516600625 = 264534^2 + 252025^2 .

It is a cyclic number.

It is not a de Polignac number, because 133494837781 - 2¹ = 133494837779 is a prime.

It is a super-2 number, since 2×133494837781² (a number of 23 digits) contains 22 as substring.

Together with 133494837779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (133494837701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66747418890 + 66747418891.

It is an arithmetic number, because the mean of its divisors is an integer number (66747418891).

Almost surely, 2^133494837781 is an apocalyptic number.

It is an amenable number.

133494837781 is a deficient number, since it is larger than the sum of its proper divisors (1).

133494837781 is an equidigital number, since it uses as much as digits as its factorization.

133494837781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12192768, while the sum is 58.

The spelling of 133494837781 in words is "one hundred thirty-three billion, four hundred ninety-four million, eight hundred thirty-seven thousand, seven hundred eighty-one".