6557777556 has 96 divisors (see below), whose sum is σ = 17042659200. Its totient is φ = 1945681920.

The previous prime is 6557777533. The next prime is 6557777579.

It is a happy number.

6557777556 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (6557777533) and next prime (6557777579).

It is a self number, because there is not a number n which added to its sum of digits gives 6557777556.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6498780 + ... + 6499788.

It is an arithmetic number, because the mean of its divisors is an integer number (177527700).

Almost surely, 2^6557777556 is an apocalyptic number.

6557777556 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6557777556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8521329600).

6557777556 is an abundant number, since it is smaller than the sum of its proper divisors (10484881644).

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

6557777556 is a wasteful number, since it uses less digits than its factorization.

6557777556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009 (or 2007 counting only the distinct ones).

The product of its digits is 54022500, while the sum is 60.

The square root of 6557777556 is about 80980.1059273202. The cubic root of 6557777556 is about 1871.7688997626.

The spelling of 6557777556 in words is "six billion, five hundred fifty-seven million, seven hundred seventy-seven thousand, five hundred fifty-six".