1663981322116 has 9 divisors (see below), whose sum is σ = 2911971828549. Its totient is φ = 831989371104.

The previous prime is 1663981322093. The next prime is 1663981322123. The reversal of 1663981322116 is 6112231893661.

The square root of 1663981322116 is 1289954.

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., 992394516100 + 671586806016 = 996190^2 + 819504^2 .

It is a super-2 number, since 2×1663981322116² (a number of 25 digits) contains 22 as substring.

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 1663981322116.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 2257420 + ... + 2902396.

Almost surely, 2^{1663981322116} is an apocalyptic number.

1663981322116 is the 1289954-th square number.

It is an amenable number.

1663981322116 is a deficient number, since it is larger than the sum of its proper divisors (1247990506433).

1663981322116 is an frugal number, since it uses more digits than its factorization.

1663981322116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1289958 (or 644979 counting only the distinct ones).

The product of its digits is 559872, while the sum is 49.

Multiplying 1663981322116 by its sum of digits (49), we get a square (81535084783684 = 9029678²).

The spelling of 1663981322116 in words is "one trillion, six hundred sixty-three billion, nine hundred eighty-one million, three hundred twenty-two thousand, one hundred sixteen".