398026909 has 4 divisors (see below), whose sum is σ = 454887904. Its totient is φ = 341165916.

The previous prime is 398026903. The next prime is 398026927. The reversal of 398026909 is 909620893.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 398026909 - 2⁹ = 398026397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398026903) 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 in 3 ways as a sum of consecutive naturals, for example, 28430487 + ... + 28430500.

It is an arithmetic number, because the mean of its divisors is an integer number (113721976).

Almost surely, 2^398026909 is an apocalyptic number.

It is an amenable number.

398026909 is a deficient number, since it is larger than the sum of its proper divisors (56860995).

398026909 is an equidigital number, since it uses as much as digits as its factorization.

398026909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56860994.

The product of its (nonzero) digits is 209952, while the sum is 46.

The square root of 398026909 is about 19950.6117450067. The cubic root of 398026909 is about 735.5928140385.

The spelling of 398026909 in words is "three hundred ninety-eight million, twenty-six thousand, nine hundred nine".