191388133 has 4 divisors (see below), whose sum is σ = 192445708. Its totient is φ = 190330560.

The previous prime is 191388103. The next prime is 191388143. The reversal of 191388133 is 331883191.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 331883191 = 53 ⋅6261947.

It can be written as a sum of positive squares in 2 ways, for example, as 77475204 + 113912929 = 8802^2 + 10673^2 .

It is a cyclic number.

It is not a de Polignac number, because 191388133 - 2⁵ = 191388101 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 191388092 and 191388101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191388103) 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, 528516 + ... + 528877.

It is an arithmetic number, because the mean of its divisors is an integer number (48111427).

Almost surely, 2^191388133 is an apocalyptic number.

It is an amenable number.

191388133 is a deficient number, since it is larger than the sum of its proper divisors (1057575).

191388133 is a wasteful number, since it uses less digits than its factorization.

191388133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1057574.

The product of its digits is 15552, while the sum is 37.

The square root of 191388133 is about 13834.3099936354. The cubic root of 191388133 is about 576.2863531256.

The spelling of 191388133 in words is "one hundred ninety-one million, three hundred eighty-eight thousand, one hundred thirty-three".