997628661765 has 64 divisors (see below), whose sum is σ = 1777312696320. Its totient is φ = 530944657920.

The previous prime is 997628661713. The next prime is 997628661791. The reversal of 997628661765 is 567166826799.

It is not a de Polignac number, because 997628661765 - 2¹¹ = 997628659717 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 997628661693 and 997628661702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 160982647 + ... + 160988843.

It is an arithmetic number, because the mean of its divisors is an integer number (27770510880).

Almost surely, 2^997628661765 is an apocalyptic number.

It is an amenable number.

997628661765 is a deficient number, since it is larger than the sum of its proper divisors (779684034555).

997628661765 is a wasteful number, since it uses less digits than its factorization.

997628661765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8539 (or 8533 counting only the distinct ones).

The product of its digits is 411505920, while the sum is 72.

The spelling of 997628661765 in words is "nine hundred ninety-seven billion, six hundred twenty-eight million, six hundred sixty-one thousand, seven hundred sixty-five".