133688749 has 4 divisors (see below), whose sum is σ = 135954720. Its totient is φ = 131422780.

The previous prime is 133688743. The next prime is 133688767. The reversal of 133688749 is 947886331.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 133688749 - 2¹¹ = 133686701 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 (133688743) 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, 1132897 + ... + 1133014.

It is an arithmetic number, because the mean of its divisors is an integer number (33988680).

Almost surely, 2^133688749 is an apocalyptic number.

It is an amenable number.

133688749 is a deficient number, since it is larger than the sum of its proper divisors (2265971).

133688749 is an equidigital number, since it uses as much as digits as its factorization.

133688749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2265970.

The product of its digits is 870912, while the sum is 49.

The square root of 133688749 is about 11562.3850913209. The cubic root of 133688749 is about 511.3264828198.

The spelling of 133688749 in words is "one hundred thirty-three million, six hundred eighty-eight thousand, seven hundred forty-nine".