233128913 has 4 divisors (see below), whose sum is σ = 233295780. Its totient is φ = 232962048.

The previous prime is 233128901. The next prime is 233128919. The reversal of 233128913 is 319821332.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1723969 + 231404944 = 1313^2 + 15212^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-233128913 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 233128913.

It is not an unprimeable number, because it can be changed into a prime (233128919) 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, 81320 + ... + 84137.

It is an arithmetic number, because the mean of its divisors is an integer number (58323945).

Almost surely, 2^233128913 is an apocalyptic number.

It is an amenable number.

233128913 is a deficient number, since it is larger than the sum of its proper divisors (166867).

233128913 is a wasteful number, since it uses less digits than its factorization.

233128913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166866.

The product of its digits is 7776, while the sum is 32.

The square root of 233128913 is about 15268.5596242737. The cubic root of 233128913 is about 615.4584133696.

The spelling of 233128913 in words is "two hundred thirty-three million, one hundred twenty-eight thousand, nine hundred thirteen".