133540823 has 4 divisors (see below), whose sum is σ = 143813208. Its totient is φ = 123268440.

The previous prime is 133540817. The next prime is 133540837. The reversal of 133540823 is 328045331.

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

It is a cyclic number.

It is not a de Polignac number, because 133540823 - 2²⁰ = 132492247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133540523) 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, 5136173 + ... + 5136198.

It is an arithmetic number, because the mean of its divisors is an integer number (35953302).

Almost surely, 2^133540823 is an apocalyptic number.

133540823 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

133540823 is a deficient number, since it is larger than the sum of its proper divisors (10272385).

133540823 is a wasteful number, since it uses less digits than its factorization.

133540823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10272384.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 133540823 is about 11555.9864572437. The cubic root of 133540823 is about 511.1378197326.

The spelling of 133540823 in words is "one hundred thirty-three million, five hundred forty thousand, eight hundred twenty-three".