133391691 has 26 divisors (see below), whose sum is σ = 200884572. Its totient is φ = 88573500.

The previous prime is 133391683. The next prime is 133391701. The reversal of 133391691 is 196193331.

It is not a de Polignac number, because 133391691 - 2³ = 133391683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (133391681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 25 ways as a sum of consecutive naturals, for example, 531316 + ... + 531566.

Almost surely, 2^133391691 is an apocalyptic number.

133391691 is a deficient number, since it is larger than the sum of its proper divisors (67492881).

133391691 is an frugal number, since it uses more digits than its factorization.

133391691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287 (or 254 counting only the distinct ones).

The product of its digits is 13122, while the sum is 36.

The square root of 133391691 is about 11549.5320684433. The cubic root of 133391691 is about 510.9474774417.

The spelling of 133391691 in words is "one hundred thirty-three million, three hundred ninety-one thousand, six hundred ninety-one".