6404391999 has 6 divisors (see below), whose sum is σ = 9250788456. Its totient is φ = 4269594660.

The previous prime is 6404391977. The next prime is 6404392009. The reversal of 6404391999 is 9991934046.

It is not a de Polignac number, because 6404391999 - 2⁸ = 6404391743 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6404391919) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 355799547 + ... + 355799564.

It is an arithmetic number, because the mean of its divisors is an integer number (1541798076).

Almost surely, 2^6404391999 is an apocalyptic number.

6404391999 is a deficient number, since it is larger than the sum of its proper divisors (2846396457).

6404391999 is a wasteful number, since it uses less digits than its factorization.

6404391999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 711599117 (or 711599114 counting only the distinct ones).

The product of its (nonzero) digits is 1889568, while the sum is 54.

The square root of 6404391999 is about 80027.4452859767. The cubic root of 6404391999 is about 1857.0601416124.

The spelling of 6404391999 in words is "six billion, four hundred four million, three hundred ninety-one thousand, nine hundred ninety-nine".