661051663365445 has 8 divisors (see below), whose sum is σ = 865376722951200. Its totient is φ = 480764846083920.

The previous prime is 661051663365439. The next prime is 661051663365481. The reversal of 661051663365445 is 544563366150166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 661051663365445 - 2⁵ = 661051663365413 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6009560575995 + ... + 6009560576104.

It is an arithmetic number, because the mean of its divisors is an integer number (108172090368900).

Almost surely, 2^{661051663365445} is an apocalyptic number.

It is an amenable number.

661051663365445 is a deficient number, since it is larger than the sum of its proper divisors (204325059585755).

661051663365445 is a wasteful number, since it uses less digits than its factorization.

661051663365445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12019121152115.

The product of its (nonzero) digits is 139968000, while the sum is 61.

The spelling of 661051663365445 in words is "six hundred sixty-one trillion, fifty-one billion, six hundred sixty-three million, three hundred sixty-five thousand, four hundred forty-five".