1643993240084 has 48 divisors (see below), whose sum is σ = 3187329459216. Its totient is φ = 737030016000.

The previous prime is 1643993240081. The next prime is 1643993240167. The reversal of 1643993240084 is 4800423993461.

It can be written as a sum of positive squares in 8 ways, for example, as 246462602500 + 1397530637584 = 496450^2 + 1182172^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643993240081) 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, 445454 + ... + 1867194.

It is an arithmetic number, because the mean of its divisors is an integer number (66402697067).

Almost surely, 2^{1643993240084} is an apocalyptic number.

It is an amenable number.

1643993240084 is a deficient number, since it is larger than the sum of its proper divisors (1543336219132).

1643993240084 is a wasteful number, since it uses less digits than its factorization.

1643993240084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1422396 (or 1422394 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 53.

The spelling of 1643993240084 in words is "one trillion, six hundred forty-three billion, nine hundred ninety-three million, two hundred forty thousand, eighty-four".