16561766992 has 10 divisors (see below), whose sum is σ = 32088423578. Its totient is φ = 8280883488.

The previous prime is 16561766981. The next prime is 16561766999. The reversal of 16561766992 is 29966716561.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 13643174416 + 2918592576 = 116804^2 + 54024^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16561766999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 517555203 + ... + 517555234.

Almost surely, 2^16561766992 is an apocalyptic number.

It is an amenable number.

16561766992 is a deficient number, since it is larger than the sum of its proper divisors (15526656586).

16561766992 is a wasteful number, since it uses less digits than its factorization.

16561766992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1035110445 (or 1035110439 counting only the distinct ones).

The product of its digits is 7348320, while the sum is 58.

The spelling of 16561766992 in words is "sixteen billion, five hundred sixty-one million, seven hundred sixty-six thousand, nine hundred ninety-two".