1320661611 has 16 divisors (see below), whose sum is σ = 1961881600. Its totient is φ = 878035464.

The previous prime is 1320661591. The next prime is 1320661631. The reversal of 1320661611 is 1161660231.

1320661611 is a `hidden beast` number, since 1 + 32 + 0 + 6 + 616 + 11 = 666.

It is an interprime number because it is at equal distance from previous prime (1320661591) and next prime (1320661631).

It is not a de Polignac number, because 1320661611 - 2⁶ = 1320661547 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1320661631) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 56731 + ... + 76548.

It is an arithmetic number, because the mean of its divisors is an integer number (122617600).

Almost surely, 2^1320661611 is an apocalyptic number.

1320661611 is a deficient number, since it is larger than the sum of its proper divisors (641219989).

1320661611 is a wasteful number, since it uses less digits than its factorization.

1320661611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133655 (or 133649 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 1320661611 is about 36340.9082302575. The cubic root of 1320661611 is about 1097.1445530239.

The spelling of 1320661611 in words is "one billion, three hundred twenty million, six hundred sixty-one thousand, six hundred eleven".