665471947 has 8 divisors (see below), whose sum is σ = 785073152. Its totient is φ = 552004200.

The previous prime is 665471929. The next prime is 665471951. The reversal of 665471947 is 749174566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 665471947 - 2¹¹ = 665469899 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 665471947.

It is not an unprimeable number, because it can be changed into a prime (665474947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1533129 + ... + 1533562.

It is an arithmetic number, because the mean of its divisors is an integer number (98134144).

Almost surely, 2^665471947 is an apocalyptic number.

665471947 is a deficient number, since it is larger than the sum of its proper divisors (119601205).

665471947 is a wasteful number, since it uses less digits than its factorization.

665471947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3066729.

The product of its digits is 1270080, while the sum is 49.

The square root of 665471947 is about 25796.7429533265. The cubic root of 665471947 is about 873.0583108174.

The spelling of 665471947 in words is "six hundred sixty-five million, four hundred seventy-one thousand, nine hundred forty-seven".