320612405661 has 64 divisors (see below), whose sum is σ = 492992179200. Its totient is φ = 205764245568.

The previous prime is 320612405657. The next prime is 320612405741. The reversal of 320612405661 is 166504216023.

320612405661 is a `hidden beast` number, since 32 + 0 + 61 + 2 + 4 + 0 + 566 + 1 = 666.

It is not a de Polignac number, because 320612405661 - 2² = 320612405657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320612405621) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 124315270 + ... + 124317848.

It is an arithmetic number, because the mean of its divisors is an integer number (7703002800).

Almost surely, 2^320612405661 is an apocalyptic number.

It is an amenable number.

320612405661 is a deficient number, since it is larger than the sum of its proper divisors (172379773539).

320612405661 is a wasteful number, since it uses less digits than its factorization.

320612405661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3895 (or 3889 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 320612405661 in words is "three hundred twenty billion, six hundred twelve million, four hundred five thousand, six hundred sixty-one".