6399923870 has 64 divisors (see below), whose sum is σ = 12791675520. Its totient is φ = 2294304768.

The previous prime is 6399923863. The next prime is 6399923879. The reversal of 6399923870 is 783299936.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6399923879) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 350999 + ... + 368781.

It is an arithmetic number, because the mean of its divisors is an integer number (199869930).

Almost surely, 2^6399923870 is an apocalyptic number.

6399923870 is a deficient number, since it is larger than the sum of its proper divisors (6391751650).

6399923870 is a wasteful number, since it uses less digits than its factorization.

6399923870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17909.

The product of its (nonzero) digits is 4408992, while the sum is 56.

The square root of 6399923870 is about 79999.5241860850. The cubic root of 6399923870 is about 1856.6281716626.

The spelling of 6399923870 in words is "six billion, three hundred ninety-nine million, nine hundred twenty-three thousand, eight hundred seventy".