7181681777956 has 81 divisors (see below), whose sum is σ = 14846512295601. Its totient is φ = 3030864129216.

The previous prime is 7181681777951. The next prime is 7181681778017. The reversal of 7181681777956 is 6597771861817.

The square root of 7181681777956 is 2679866.

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

It can be written as a sum of positive squares in only one way, i.e., 4838284152100 + 2343397625856 = 2199610^2 + 1530816^2 .

It is not an unprimeable number, because it can be changed into a prime (7181681777951) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2513712880 + ... + 2513715736.

Almost surely, 2^{7181681777956} is an apocalyptic number.

7181681777956 is the 2679866-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7181681777956

7181681777956 is an abundant number, since it is smaller than the sum of its proper divisors (7664830517645).

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

7181681777956 is an frugal number, since it uses more digits than its factorization.

7181681777956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5866 (or 2933 counting only the distinct ones).

The product of its digits is 248935680, while the sum is 73.

The spelling of 7181681777956 in words is "seven trillion, one hundred eighty-one billion, six hundred eighty-one million, seven hundred seventy-seven thousand, nine hundred fifty-six".