1643065947256 has 16 divisors (see below), whose sum is σ = 3080782089000. Its totient is φ = 821524056864.

The previous prime is 1643065947251. The next prime is 1643065947277. The reversal of 1643065947256 is 6527495603461.

It is a self number, because there is not a number n which added to its sum of digits gives 1643065947256.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643065947251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 296106 + ... + 1836793.

Almost surely, 2^{1643065947256} is an apocalyptic number.

It is an amenable number.

1643065947256 is a deficient number, since it is larger than the sum of its proper divisors (1437716141744).

1643065947256 is a wasteful number, since it uses less digits than its factorization.

1643065947256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2229198 (or 2229194 counting only the distinct ones).

The product of its (nonzero) digits is 32659200, while the sum is 58.

The spelling of 1643065947256 in words is "one trillion, six hundred forty-three billion, sixty-five million, nine hundred forty-seven thousand, two hundred fifty-six".