238107721 has 2 divisors, whose sum is σ = 238107722. Its totient is φ = 238107720.

The previous prime is 238107713. The next prime is 238107731. The reversal of 238107721 is 127701832.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187142400 + 50965321 = 13680^2 + 7139^2 .

It is a cyclic number.

It is not a de Polignac number, because 238107721 - 2³ = 238107713 is a prime.

It is not a weakly prime, because it can be changed into another prime (238107731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119053860 + 119053861.

It is an arithmetic number, because the mean of its divisors is an integer number (119053861).

Almost surely, 2^238107721 is an apocalyptic number.

It is an amenable number.

238107721 is a deficient number, since it is larger than the sum of its proper divisors (1).

238107721 is an equidigital number, since it uses as much as digits as its factorization.

238107721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 238107721 is about 15430.7394832523. The cubic root of 238107721 is about 619.8089256846.

The spelling of 238107721 in words is "two hundred thirty-eight million, one hundred seven thousand, seven hundred twenty-one".