6399381356 has 24 divisors (see below), whose sum is σ = 11725759584. Its totient is φ = 3050115200.

The previous prime is 6399381353. The next prime is 6399381371. The reversal of 6399381356 is 6531839936.

It is a junction number, because it is equal to n+sod(n) for n = 6399381298 and 6399381307.

It is not an unprimeable number, because it can be changed into a prime (6399381353) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91745 + ... + 145656.

It is an arithmetic number, because the mean of its divisors is an integer number (488573316).

Almost surely, 2^6399381356 is an apocalyptic number.

It is an amenable number.

6399381356 is a deficient number, since it is larger than the sum of its proper divisors (5326378228).

6399381356 is a wasteful number, since it uses less digits than its factorization.

6399381356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237721 (or 237719 counting only the distinct ones).

The product of its digits is 3149280, while the sum is 53.

The square root of 6399381356 is about 79996.1333815579. The cubic root of 6399381356 is about 1856.5757087866.

The spelling of 6399381356 in words is "six billion, three hundred ninety-nine million, three hundred eighty-one thousand, three hundred fifty-six".