1997659984996 has 27 divisors (see below), whose sum is σ = 3785576206923. Its totient is φ = 921979955520.

The previous prime is 1997659984973. The next prime is 1997659985093. The reversal of 1997659984996 is 6994899567991.

The square root of 1997659984996 is 1413386.

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

It can be written as a sum of positive squares in 4 ways, for example, as 180922622500 + 1816737362496 = 425350^2 + 1347864^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1997659984996.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 36720856 + ... + 36775216.

Almost surely, 2^{1997659984996} is an apocalyptic number.

1997659984996 is the 1413386-th square number.

It is an amenable number.

1997659984996 is a deficient number, since it is larger than the sum of its proper divisors (1787916221927).

1997659984996 is an frugal number, since it uses more digits than its factorization.

1997659984996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108752 (or 54376 counting only the distinct ones).

The product of its digits is 21427701120, while the sum is 91.

The spelling of 1997659984996 in words is "one trillion, nine hundred ninety-seven billion, six hundred fifty-nine million, nine hundred eighty-four thousand, nine hundred ninety-six".