6399820425 has 48 divisors (see below), whose sum is σ = 11247619392. Its totient is φ = 3199795200.

The previous prime is 6399820423. The next prime is 6399820439. The reversal of 6399820425 is 5240289936.

It is a happy number.

It is not a de Polignac number, because 6399820425 - 2¹ = 6399820423 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6399820423) 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 47 ways as a sum of consecutive naturals, for example, 317910 + ... + 337440.

It is an arithmetic number, because the mean of its divisors is an integer number (234325404).

Almost surely, 2^6399820425 is an apocalyptic number.

It is an amenable number.

6399820425 is a deficient number, since it is larger than the sum of its proper divisors (4847798967).

6399820425 is a wasteful number, since it uses less digits than its factorization.

6399820425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19818 (or 19813 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 48.

The square root of 6399820425 is about 79998.8776483770. The cubic root of 6399820425 is about 1856.6181684220.

The spelling of 6399820425 in words is "six billion, three hundred ninety-nine million, eight hundred twenty thousand, four hundred twenty-five".