6720420400 has 60 divisors (see below), whose sum is σ = 16302665392. Its totient is φ = 2662053120.

The previous prime is 6720420391. The next prime is 6720420401. The reversal of 6720420400 is 40240276.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (6720420401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40359 + ... + 122758.

Almost surely, 2^6720420400 is an apocalyptic number.

It is an amenable number.

6720420400 is an abundant number, since it is smaller than the sum of its proper divisors (9582244992).

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

6720420400 is a wasteful number, since it uses less digits than its factorization.

6720420400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163238 (or 163227 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 6720420400 is about 81978.1702650163. The cubic root of 6720420400 is about 1887.1169428646.

Adding to 6720420400 its reverse (40240276), we get a palindrome (6760660676).

The spelling of 6720420400 in words is "six billion, seven hundred twenty million, four hundred twenty thousand, four hundred".