133481281 has 4 divisors (see below), whose sum is σ = 136736964. Its totient is φ = 130225600.

The previous prime is 133481279. The next prime is 133481317. The reversal of 133481281 is 182184331.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 78854400 + 54626881 = 8880^2 + 7391^2 .

It is a cyclic number.

It is not a de Polignac number, because 133481281 - 2¹ = 133481279 is a prime.

It is a super-2 number, since 2×133481281² = 35634504754801922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133481981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1627780 + ... + 1627861.

It is an arithmetic number, because the mean of its divisors is an integer number (34184241).

Almost surely, 2^133481281 is an apocalyptic number.

It is an amenable number.

133481281 is a deficient number, since it is larger than the sum of its proper divisors (3255683).

133481281 is an equidigital number, since it uses as much as digits as its factorization.

133481281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3255682.

The product of its digits is 4608, while the sum is 31.

The square root of 133481281 is about 11553.4099295403. The cubic root of 133481281 is about 511.0618412371.

The spelling of 133481281 in words is "one hundred thirty-three million, four hundred eighty-one thousand, two hundred eighty-one".