398126789 has 2 divisors, whose sum is σ = 398126790. Its totient is φ = 398126788.

The previous prime is 398126759. The next prime is 398126821. The reversal of 398126789 is 987621893.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 357588100 + 40538689 = 18910^2 + 6367^2 .

It is a cyclic number.

It is not a de Polignac number, because 398126789 - 2¹² = 398122693 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 398126789.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398126759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199063394 + 199063395.

It is an arithmetic number, because the mean of its divisors is an integer number (199063395).

Almost surely, 2^398126789 is an apocalyptic number.

It is an amenable number.

398126789 is a deficient number, since it is larger than the sum of its proper divisors (1).

398126789 is an equidigital number, since it uses as much as digits as its factorization.

398126789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 53.

The square root of 398126789 is about 19953.1147693787. The cubic root of 398126789 is about 735.6543382419.

The spelling of 398126789 in words is "three hundred ninety-eight million, one hundred twenty-six thousand, seven hundred eighty-nine".