133768491 has 4 divisors (see below), whose sum is σ = 178357992. Its totient is φ = 89178992.

The previous prime is 133768489. The next prime is 133768501. The reversal of 133768491 is 194867331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194867331 = 3 ⋅64955777.

It is a cyclic number.

It is not a de Polignac number, because 133768491 - 2¹ = 133768489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (133768471) 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, 22294746 + ... + 22294751.

It is an arithmetic number, because the mean of its divisors is an integer number (44589498).

Almost surely, 2^133768491 is an apocalyptic number.

133768491 is a deficient number, since it is larger than the sum of its proper divisors (44589501).

133768491 is an equidigital number, since it uses as much as digits as its factorization.

133768491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44589500.

The product of its digits is 108864, while the sum is 42.

The square root of 133768491 is about 11565.8329142349. The cubic root of 133768491 is about 511.4281271054.

The spelling of 133768491 in words is "one hundred thirty-three million, seven hundred sixty-eight thousand, four hundred ninety-one".