661108897683 has 20 divisors (see below), whose sum is σ = 1063550308128. Its totient is φ = 406836244080.

The previous prime is 661108897643. The next prime is 661108897699. The reversal of 661108897683 is 386798801166.

661108897683 is a `hidden beast` number, since 6 + 611 + 0 + 8 + 8 + 9 + 7 + 6 + 8 + 3 = 666.

It is not a de Polignac number, because 661108897683 - 2⁹ = 661108897171 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 661108897683.

It is not an unprimeable number, because it can be changed into a prime (661108897643) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 313915803 + ... + 313917908.

Almost surely, 2^661108897683 is an apocalyptic number.

661108897683 is a deficient number, since it is larger than the sum of its proper divisors (402441410445).

661108897683 is a wasteful number, since it uses less digits than its factorization.

661108897683 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 627833736 (or 627833727 counting only the distinct ones).

The product of its (nonzero) digits is 20901888, while the sum is 63.

The spelling of 661108897683 in words is "six hundred sixty-one billion, one hundred eight million, eight hundred ninety-seven thousand, six hundred eighty-three".