6638877220 has 12 divisors (see below), whose sum is σ = 13941642204. Its totient is φ = 2655550880.

The previous prime is 6638877187. The next prime is 6638877241. The reversal of 6638877220 is 227788366.

It can be written as a sum of positive squares in 2 ways, for example, as 3789879844 + 2848997376 = 61562^2 + 53376^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 165971911 + ... + 165971950.

It is an arithmetic number, because the mean of its divisors is an integer number (1161803517).

Almost surely, 2^6638877220 is an apocalyptic number.

It is an amenable number.

6638877220 is an abundant number, since it is smaller than the sum of its proper divisors (7302764984).

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

6638877220 is a wasteful number, since it uses less digits than its factorization.

6638877220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331943870 (or 331943868 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 49.

The square root of 6638877220 is about 81479.3054707758. The cubic root of 6638877220 is about 1879.4533286793.

The spelling of 6638877220 in words is "six billion, six hundred thirty-eight million, eight hundred seventy-seven thousand, two hundred twenty".