661541053105 has 4 divisors (see below), whose sum is σ = 793849263732. Its totient is φ = 529232842480.

The previous prime is 661541053051. The next prime is 661541053169. The reversal of 661541053105 is 501350145166.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 496090609569 + 165450443536 = 704337^2 + 406756^2 .

It is not a de Polignac number, because 661541053105 - 2⁹ = 661541052593 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66154105306 + ... + 66154105315.

It is an arithmetic number, because the mean of its divisors is an integer number (198462315933).

Almost surely, 2^661541053105 is an apocalyptic number.

It is an amenable number.

661541053105 is a deficient number, since it is larger than the sum of its proper divisors (132308210627).

661541053105 is a wasteful number, since it uses less digits than its factorization.

661541053105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132308210626.

The product of its (nonzero) digits is 54000, while the sum is 37.

The spelling of 661541053105 in words is "six hundred sixty-one billion, five hundred forty-one million, fifty-three thousand, one hundred five".