661555506662 has 16 divisors (see below), whose sum is σ = 1007476013232. Its totient is φ = 325733422080.

The previous prime is 661555506643. The next prime is 661555506779. The reversal of 661555506662 is 266605555166.

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, 404243 + ... + 1219230.

It is an arithmetic number, because the mean of its divisors is an integer number (62967250827).

Almost surely, 2^661555506662 is an apocalyptic number.

661555506662 is a deficient number, since it is larger than the sum of its proper divisors (345920506570).

661555506662 is a wasteful number, since it uses less digits than its factorization.

661555506662 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1626583.

The product of its (nonzero) digits is 9720000, while the sum is 53.

The spelling of 661555506662 in words is "six hundred sixty-one billion, five hundred fifty-five million, five hundred six thousand, six hundred sixty-two".