238787618221 has 2 divisors, whose sum is σ = 238787618222. Its totient is φ = 238787618220.

The previous prime is 238787618161. The next prime is 238787618243. The reversal of 238787618221 is 122816787832.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125124912900 + 113662705321 = 353730^2 + 337139^2 .

It is a cyclic number.

It is not a de Polignac number, because 238787618221 - 2¹⁵ = 238787585453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (238787618521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119393809110 + 119393809111.

It is an arithmetic number, because the mean of its divisors is an integer number (119393809111).

Almost surely, 2^238787618221 is an apocalyptic number.

It is an amenable number.

238787618221 is a deficient number, since it is larger than the sum of its proper divisors (1).

238787618221 is an equidigital number, since it uses as much as digits as its factorization.

238787618221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3612672, while the sum is 55.

The spelling of 238787618221 in words is "two hundred thirty-eight billion, seven hundred eighty-seven million, six hundred eighteen thousand, two hundred twenty-one".