398783639 has 2 divisors, whose sum is σ = 398783640. Its totient is φ = 398783638.

The previous prime is 398783629. The next prime is 398783663. The reversal of 398783639 is 936387893.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 398783639 - 2⁸ = 398783383 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398783629) 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, 199391819 + 199391820.

It is an arithmetic number, because the mean of its divisors is an integer number (199391820).

Almost surely, 2^398783639 is an apocalyptic number.

398783639 is a deficient number, since it is larger than the sum of its proper divisors (1).

398783639 is an equidigital number, since it uses as much as digits as its factorization.

398783639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5878656, while the sum is 56.

The square root of 398783639 is about 19969.5678220637. The cubic root of 398783639 is about 736.0586893722.

The spelling of 398783639 in words is "three hundred ninety-eight million, seven hundred eighty-three thousand, six hundred thirty-nine".