1681571851872 has 72 divisors (see below), whose sum is σ = 4851890717688. Its totient is φ = 509567224320.

The previous prime is 1681571851849. The next prime is 1681571851909. The reversal of 1681571851872 is 2781581751861.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72370093 + ... + 72393324.

It is an arithmetic number, because the mean of its divisors is an integer number (67387371079).

Almost surely, 2^{1681571851872} is an apocalyptic number.

1681571851872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1681571851872 is an abundant number, since it is smaller than the sum of its proper divisors (3170318865816).

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

1681571851872 is a wasteful number, since it uses less digits than its factorization.

1681571851872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144763452 (or 144763433 counting only the distinct ones).

The product of its digits is 7526400, while the sum is 60.

The spelling of 1681571851872 in words is "one trillion, six hundred eighty-one billion, five hundred seventy-one million, eight hundred fifty-one thousand, eight hundred seventy-two".