6653121872 has 20 divisors (see below), whose sum is σ = 12891776436. Its totient is φ = 3326211840.

The previous prime is 6653121869. The next prime is 6653121877. The reversal of 6653121872 is 2781213566.

It can be written as a sum of positive squares in 2 ways, for example, as 2185001536 + 4468120336 = 46744^2 + 66844^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6653121877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210122 + ... + 239702.

Almost surely, 2^6653121872 is an apocalyptic number.

It is an amenable number.

6653121872 is a deficient number, since it is larger than the sum of its proper divisors (6238654564).

6653121872 is a wasteful number, since it uses less digits than its factorization.

6653121872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43646 (or 43640 counting only the distinct ones).

The product of its digits is 120960, while the sum is 41.

The square root of 6653121872 is about 81566.6713308812. The cubic root of 6653121872 is about 1880.7965795886.

The spelling of 6653121872 in words is "six billion, six hundred fifty-three million, one hundred twenty-one thousand, eight hundred seventy-two".