438381857 has 2 divisors, whose sum is σ = 438381858. Its totient is φ = 438381856.

The previous prime is 438381821. The next prime is 438381887. The reversal of 438381857 is 758183834.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 421727296 + 16654561 = 20536^2 + 4081^2 .

It is a cyclic number.

It is not a de Polignac number, because 438381857 - 2¹² = 438377761 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (438381887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 219190928 + 219190929.

It is an arithmetic number, because the mean of its divisors is an integer number (219190929).

Almost surely, 2^438381857 is an apocalyptic number.

It is an amenable number.

438381857 is a deficient number, since it is larger than the sum of its proper divisors (1).

438381857 is an equidigital number, since it uses as much as digits as its factorization.

438381857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 645120, while the sum is 47.

The square root of 438381857 is about 20937.5704655531. The cubic root of 438381857 is about 759.6569648810.

The spelling of 438381857 in words is "four hundred thirty-eight million, three hundred eighty-one thousand, eight hundred fifty-seven".