133723906 has 4 divisors (see below), whose sum is σ = 200585862. Its totient is φ = 66861952.

The previous prime is 133723903. The next prime is 133723907. The reversal of 133723906 is 609327331.

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

It can be written as a sum of positive squares in only one way, i.e., 113103225 + 20620681 = 10635^2 + 4541^2 .

It is not an unprimeable number, because it can be changed into a prime (133723903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33430975 + ... + 33430978.

Almost surely, 2^133723906 is an apocalyptic number.

133723906 is a deficient number, since it is larger than the sum of its proper divisors (66861956).

133723906 is an equidigital number, since it uses as much as digits as its factorization.

133723906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66861955.

The product of its (nonzero) digits is 20412, while the sum is 34.

The square root of 133723906 is about 11563.9053091938. The cubic root of 133723906 is about 511.3713011751.

The spelling of 133723906 in words is "one hundred thirty-three million, seven hundred twenty-three thousand, nine hundred six".