238784921 has 2 divisors, whose sum is σ = 238784922. Its totient is φ = 238784920.

The previous prime is 238784813. The next prime is 238784963. The reversal of 238784921 is 129487832.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 218714521 + 20070400 = 14789^2 + 4480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-238784921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (238780921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119392460 + 119392461.

It is an arithmetic number, because the mean of its divisors is an integer number (119392461).

Almost surely, 2^238784921 is an apocalyptic number.

It is an amenable number.

238784921 is a deficient number, since it is larger than the sum of its proper divisors (1).

238784921 is an equidigital number, since it uses as much as digits as its factorization.

238784921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 193536, while the sum is 44.

The square root of 238784921 is about 15452.6671160677. The cubic root of 238784921 is about 620.3959671423.

The spelling of 238784921 in words is "two hundred thirty-eight million, seven hundred eighty-four thousand, nine hundred twenty-one".