133381811 has 4 divisors (see below), whose sum is σ = 133564512. Its totient is φ = 133199112.

The previous prime is 133381799. The next prime is 133381819. The reversal of 133381811 is 118183331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 118183331 = 7 ⋅16883333.

It is a cyclic number.

It is not a de Polignac number, because 133381811 - 2¹⁰ = 133380787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133381819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90251 + ... + 91716.

It is an arithmetic number, because the mean of its divisors is an integer number (33391128).

Almost surely, 2^133381811 is an apocalyptic number.

133381811 is a deficient number, since it is larger than the sum of its proper divisors (182701).

133381811 is an equidigital number, since it uses as much as digits as its factorization.

133381811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182700.

The product of its digits is 1728, while the sum is 29.

The square root of 133381811 is about 11549.1043375666. The cubic root of 133381811 is about 510.9348622489.

The spelling of 133381811 in words is "one hundred thirty-three million, three hundred eighty-one thousand, eight hundred eleven".