6721055138 has 32 divisors (see below), whose sum is σ = 12013056000. Its totient is φ = 2759206464.

The previous prime is 6721055129. The next prime is 6721055171. The reversal of 6721055138 is 8315501276.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13613 + ... + 116736.

It is an arithmetic number, because the mean of its divisors is an integer number (375408000).

Almost surely, 2^6721055138 is an apocalyptic number.

6721055138 is a deficient number, since it is larger than the sum of its proper divisors (5292000862).

6721055138 is a wasteful number, since it uses less digits than its factorization.

6721055138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130514.

The product of its (nonzero) digits is 50400, while the sum is 38.

The square root of 6721055138 is about 81982.0415578924. The cubic root of 6721055138 is about 1887.1763531918.

The spelling of 6721055138 in words is "six billion, seven hundred twenty-one million, fifty-five thousand, one hundred thirty-eight".