233643989 has 2 divisors, whose sum is σ = 233643990. Its totient is φ = 233643988.

The previous prime is 233643979. The next prime is 233644009. The reversal of 233643989 is 989346332.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220284964 + 13359025 = 14842^2 + 3655^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-233643989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (233643929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 116821994 + 116821995.

It is an arithmetic number, because the mean of its divisors is an integer number (116821995).

Almost surely, 2^233643989 is an apocalyptic number.

It is an amenable number.

233643989 is a deficient number, since it is larger than the sum of its proper divisors (1).

233643989 is an equidigital number, since it uses as much as digits as its factorization.

233643989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 839808, while the sum is 47.

The square root of 233643989 is about 15285.4175278270. The cubic root of 233643989 is about 615.9113454314.

The spelling of 233643989 in words is "two hundred thirty-three million, six hundred forty-three thousand, nine hundred eighty-nine".