398806769 has 2 divisors, whose sum is σ = 398806770. Its totient is φ = 398806768.

The previous prime is 398806711. The next prime is 398806781. The reversal of 398806769 is 967608893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 252396769 + 146410000 = 15887^2 + 12100^2 .

It is a cyclic number.

It is not a de Polignac number, because 398806769 - 2¹² = 398802673 is a prime.

It is a super-2 number, since 2×398806769² = 318093678000438722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (398806799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199403384 + 199403385.

It is an arithmetic number, because the mean of its divisors is an integer number (199403385).

Almost surely, 2^398806769 is an apocalyptic number.

It is an amenable number.

398806769 is a deficient number, since it is larger than the sum of its proper divisors (1).

398806769 is an equidigital number, since it uses as much as digits as its factorization.

398806769 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3919104, while the sum is 56.

The square root of 398806769 is about 19970.1469448775. The cubic root of 398806769 is about 736.0729199028.

The spelling of 398806769 in words is "three hundred ninety-eight million, eight hundred six thousand, seven hundred sixty-nine".