1643193731388 has 48 divisors (see below), whose sum is σ = 4233068654976. Its totient is φ = 491938244160.

The previous prime is 1643193731359. The next prime is 1643193731437. The reversal of 1643193731388 is 8831373913461.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74979631 + ... + 75001542.

It is an arithmetic number, because the mean of its divisors is an integer number (88188930312).

Almost surely, 2^{1643193731388} is an apocalyptic number.

It is an amenable number.

1643193731388 is an abundant number, since it is smaller than the sum of its proper divisors (2589874923588).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1643193731388 is a wasteful number, since it uses less digits than its factorization.

1643193731388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149981274 (or 149981272 counting only the distinct ones).

The product of its digits is 7838208, while the sum is 57.

The spelling of 1643193731388 in words is "one trillion, six hundred forty-three billion, one hundred ninety-three million, seven hundred thirty-one thousand, three hundred eighty-eight".