6541555977 has 16 divisors (see below), whose sum is σ = 10572212160. Its totient is φ = 3964579200.

The previous prime is 6541555963. The next prime is 6541555991. The reversal of 6541555977 is 7795551456.

6541555977 is a `hidden beast` number, since 6 + 5 + 4 + 15 + 559 + 77 = 666.

6541555977 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6541555963) and next prime (6541555991).

It is not a de Polignac number, because 6541555977 - 2¹⁴ = 6541539593 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6541555777) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11012424 + ... + 11013017.

It is an arithmetic number, because the mean of its divisors is an integer number (660763260).

Almost surely, 2^6541555977 is an apocalyptic number.

It is an amenable number.

6541555977 is a deficient number, since it is larger than the sum of its proper divisors (4030656183).

6541555977 is a wasteful number, since it uses less digits than its factorization.

6541555977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22025461 (or 22025455 counting only the distinct ones).

The product of its digits is 6615000, while the sum is 54.

The square root of 6541555977 is about 80879.8861089703. The cubic root of 6541555977 is about 1870.2242648093.

The spelling of 6541555977 in words is "six billion, five hundred forty-one million, five hundred fifty-five thousand, nine hundred seventy-seven".