1667446561 has 16 divisors (see below), whose sum is σ = 1864304640. Its totient is φ = 1478247120.

The previous prime is 1667446537. The next prime is 1667446579. The reversal of 1667446561 is 1656447661.

It is not a de Polignac number, because 1667446561 - 2⁹ = 1667446049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1667446531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 337636 + ... + 342538.

It is an arithmetic number, because the mean of its divisors is an integer number (116519040).

Almost surely, 2^1667446561 is an apocalyptic number.

1667446561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1667446561 is a deficient number, since it is larger than the sum of its proper divisors (196858079).

1667446561 is a wasteful number, since it uses less digits than its factorization.

1667446561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5676.

The product of its digits is 725760, while the sum is 46.

The square root of 1667446561 is about 40834.3796450981. The cubic root of 1667446561 is about 1185.8160060540.

The spelling of 1667446561 in words is "one billion, six hundred sixty-seven million, four hundred forty-six thousand, five hundred sixty-one".