6778555916356 has 135 divisors (see below), whose sum is σ = 14316244198557. Its totient is φ = 2808102144960.

The previous prime is 6778555916329. The next prime is 6778555916383. The reversal of 6778555916356 is 6536195558776.

The square root of 6778555916356 is 2603566.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (6778555916329) and next prime (6778555916383).

It can be written as a sum of positive squares in only one way, i.e., 6281790322500 + 496765593856 = 2506350^2 + 704816^2 .

It is a super-2 number, since 2×6778555916356² (a number of 26 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 7909633080 + ... + 7909633936.

Almost surely, 2^{6778555916356} is an apocalyptic number.

6778555916356 is the 2603566-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6778555916356

6778555916356 is an abundant number, since it is smaller than the sum of its proper divisors (7537688282201).

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

6778555916356 is an frugal number, since it uses more digits than its factorization.

6778555916356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1808 (or 897 counting only the distinct ones).

The product of its digits is 1428840000, while the sum is 73.

The spelling of 6778555916356 in words is "six trillion, seven hundred seventy-eight billion, five hundred fifty-five million, nine hundred sixteen thousand, three hundred fifty-six".