133931665 has 16 divisors (see below), whose sum is σ = 193345920. Its totient is φ = 87004800.

The previous prime is 133931659. The next prime is 133931669. The reversal of 133931665 is 566139331.

It is not a de Polignac number, because 133931665 - 2¹⁹ = 133407377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (133931669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100036 + ... + 101365.

It is an arithmetic number, because the mean of its divisors is an integer number (12084120).

Almost surely, 2^133931665 is an apocalyptic number.

It is an amenable number.

133931665 is a deficient number, since it is larger than the sum of its proper divisors (59414255).

133931665 is a wasteful number, since it uses less digits than its factorization.

133931665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201432.

The product of its digits is 43740, while the sum is 37.

The square root of 133931665 is about 11572.8849039468. The cubic root of 133931665 is about 511.6359933560.

The spelling of 133931665 in words is "one hundred thirty-three million, nine hundred thirty-one thousand, six hundred sixty-five".