6542688820 has 12 divisors (see below), whose sum is σ = 13739646564. Its totient is φ = 2617075520.

The previous prime is 6542688769. The next prime is 6542688821. The reversal of 6542688820 is 288862456.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 4578958224 + 1963730596 = 67668^2 + 44314^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6542688821) 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, 163567201 + ... + 163567240.

It is an arithmetic number, because the mean of its divisors is an integer number (1144970547).

Almost surely, 2^6542688820 is an apocalyptic number.

It is an amenable number.

6542688820 is an abundant number, since it is smaller than the sum of its proper divisors (7196957744).

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

6542688820 is a wasteful number, since it uses less digits than its factorization.

6542688820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327134450 (or 327134448 counting only the distinct ones).

The product of its (nonzero) digits is 1474560, while the sum is 49.

The square root of 6542688820 is about 80886.8890488440. The cubic root of 6542688820 is about 1870.3322181355.

The spelling of 6542688820 in words is "six billion, five hundred forty-two million, six hundred eighty-eight thousand, eight hundred twenty".