6638784420 has 24 divisors (see below), whose sum is σ = 18588596544. Its totient is φ = 1770342496.

The previous prime is 6638784419. The next prime is 6638784473. The reversal of 6638784420 is 244878366.

It is a self number, because there is not a number n which added to its sum of digits gives 6638784420.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55323144 + ... + 55323263.

It is an arithmetic number, because the mean of its divisors is an integer number (774524856).

Almost surely, 2^6638784420 is an apocalyptic number.

6638784420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6638784420 is an abundant number, since it is smaller than the sum of its proper divisors (11949812124).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6638784420 is a wasteful number, since it uses less digits than its factorization.

6638784420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110646419 (or 110646417 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 48.

The square root of 6638784420 is about 81478.7359990323. The cubic root of 6638784420 is about 1879.4445714715. Note that the first 3 decimals are identical.

The spelling of 6638784420 in words is "six billion, six hundred thirty-eight million, seven hundred eighty-four thousand, four hundred twenty".