6540396788 has 6 divisors (see below), whose sum is σ = 11445694386. Its totient is φ = 3270198392.

The previous prime is 6540396701. The next prime is 6540396887. The reversal of 6540396788 is 8876930456.

It can be written as a sum of positive squares in only one way, i.e., 5782385764 + 758011024 = 76042^2 + 27532^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 817549595 + ... + 817549602.

It is an arithmetic number, because the mean of its divisors is an integer number (1907615731).

Almost surely, 2^6540396788 is an apocalyptic number.

It is an amenable number.

6540396788 is a deficient number, since it is larger than the sum of its proper divisors (4905297598).

6540396788 is a wasteful number, since it uses less digits than its factorization.

6540396788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1635099201 (or 1635099199 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 56.

The square root of 6540396788 is about 80872.7196772805. The cubic root of 6540396788 is about 1870.1137879609.

The spelling of 6540396788 in words is "six billion, five hundred forty million, three hundred ninety-six thousand, seven hundred eighty-eight".