238430821 has 2 divisors, whose sum is σ = 238430822. Its totient is φ = 238430820.

The previous prime is 238430807. The next prime is 238430861. The reversal of 238430821 is 128034832.

238430821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 221116900 + 17313921 = 14870^2 + 4161^2 .

It is a cyclic number.

It is not a de Polignac number, because 238430821 - 2¹³ = 238422629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (238430861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119215410 + 119215411.

It is an arithmetic number, because the mean of its divisors is an integer number (119215411).

Almost surely, 2^238430821 is an apocalyptic number.

It is an amenable number.

238430821 is a deficient number, since it is larger than the sum of its proper divisors (1).

238430821 is an equidigital number, since it uses as much as digits as its factorization.

238430821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 238430821 is about 15441.2052962196. The cubic root of 238430821 is about 620.0891486446.

The spelling of 238430821 in words is "two hundred thirty-eight million, four hundred thirty thousand, eight hundred twenty-one".