661021402346012 has 12 divisors (see below), whose sum is σ = 1157565387844320. Its totient is φ = 330288434390496.

The previous prime is 661021402345973. The next prime is 661021402346077. The reversal of 661021402346012 is 210643204120166.

It is a congruent 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, 55566688937 + ... + 55566700832.

It is an arithmetic number, because the mean of its divisors is an integer number (96463782320360).

Almost surely, 2^{661021402346012} is an apocalyptic number.

It is an amenable number.

661021402346012 is a deficient number, since it is larger than the sum of its proper divisors (496543985498308).

661021402346012 is a wasteful number, since it uses less digits than its factorization.

661021402346012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111133391260 (or 111133391258 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 38.

Adding to 661021402346012 its reverse (210643204120166), we get a palindrome (871664606466178).

The spelling of 661021402346012 in words is "six hundred sixty-one trillion, twenty-one billion, four hundred two million, three hundred forty-six thousand, twelve".