233943821 has 2 divisors, whose sum is σ = 233943822. Its totient is φ = 233943820.

The previous prime is 233943739. The next prime is 233943893. The reversal of 233943821 is 128349332.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 231952900 + 1990921 = 15230^2 + 1411^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-233943821 is a prime.

It is a super-2 number, since 2×233943821² = 109459422768160082, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (233943221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 116971910 + 116971911.

It is an arithmetic number, because the mean of its divisors is an integer number (116971911).

Almost surely, 2^233943821 is an apocalyptic number.

It is an amenable number.

233943821 is a deficient number, since it is larger than the sum of its proper divisors (1).

233943821 is an equidigital number, since it uses as much as digits as its factorization.

233943821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 35.

The square root of 233943821 is about 15295.2221624924. Note that the first 3 decimals coincide. The cubic root of 233943821 is about 616.1746962283.

The spelling of 233943821 in words is "two hundred thirty-three million, nine hundred forty-three thousand, eight hundred twenty-one".