42665871656 has 32 divisors (see below), whose sum is σ = 82160605800. Its totient is φ = 20759055360.

The previous prime is 42665871649. The next prime is 42665871707. The reversal of 42665871656 is 65617856624.

It can be written as a sum of positive squares in 4 ways, for example, as 26983318756 + 15682552900 = 164266^2 + 125230^2 .

It is a Smith number, since the sum of its digits (56) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

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, 39605 + ... + 294788.

Almost surely, 2^42665871656 is an apocalyptic number.

It is an amenable number.

42665871656 is a deficient number, since it is larger than the sum of its proper divisors (39494734144).

42665871656 is a wasteful number, since it uses less digits than its factorization.

42665871656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334829 (or 334825 counting only the distinct ones).

The product of its digits is 14515200, while the sum is 56.

The spelling of 42665871656 in words is "forty-two billion, six hundred sixty-five million, eight hundred seventy-one thousand, six hundred fifty-six".