133661375 has 8 divisors (see below), whose sum is σ = 166809552. Its totient is φ = 106929000.

The previous prime is 133661369. The next prime is 133661383. The reversal of 133661375 is 573166331.

It is not a de Polignac number, because 133661375 - 2¹⁴ = 133644991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 534521 + ... + 534770.

It is an arithmetic number, because the mean of its divisors is an integer number (20851194).

Almost surely, 2^133661375 is an apocalyptic number.

133661375 is a deficient number, since it is larger than the sum of its proper divisors (33148177).

133661375 is an equidigital number, since it uses as much as digits as its factorization.

133661375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1069306 (or 1069296 counting only the distinct ones).

The product of its digits is 34020, while the sum is 35.

The square root of 133661375 is about 11561.2012784139. The cubic root of 133661375 is about 511.2915808386.

It can be divided in two parts, 13366 and 1375, that added together give a palindrome (14741).

The spelling of 133661375 in words is "one hundred thirty-three million, six hundred sixty-one thousand, three hundred seventy-five".