6561555061516 has 48 divisors (see below), whose sum is σ = 14963908389696. Its totient is φ = 2443087079424.

The previous prime is 6561555061511. The next prime is 6561555061603. The reversal of 6561555061516 is 6151605551656.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (6561555061511) 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, 530177641 + ... + 530190016.

It is an arithmetic number, because the mean of its divisors is an integer number (311748091452).

Almost surely, 2^{6561555061516} is an apocalyptic number.

It is an amenable number.

6561555061516 is an abundant number, since it is smaller than the sum of its proper divisors (8402353328180).

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

6561555061516 is a wasteful number, since it uses less digits than its factorization.

6561555061516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060367698 (or 1060367696 counting only the distinct ones).

The product of its (nonzero) digits is 4050000, while the sum is 52.

The spelling of 6561555061516 in words is "six trillion, five hundred sixty-one billion, five hundred fifty-five million, sixty-one thousand, five hundred sixteen".