123721856565648 has 160 divisors (see below), whose sum is σ = 351886439731200. Its totient is φ = 37145724940800.

The previous prime is 123721856565623. The next prime is 123721856565677. The reversal of 123721856565648 is 846565658127321.

It is a super-3 number, since 3×123721856565648³ (a number of 43 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1655791233 + ... + 1655865951.

It is an arithmetic number, because the mean of its divisors is an integer number (2199290248320).

Almost surely, 2^{123721856565648} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123721856565648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175943219865600).

123721856565648 is an abundant number, since it is smaller than the sum of its proper divisors (228164583165552).

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

123721856565648 is a wasteful number, since it uses less digits than its factorization.

123721856565648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103621 (or 103615 counting only the distinct ones).

The product of its digits is 580608000, while the sum is 69.

The spelling of 123721856565648 in words is "one hundred twenty-three trillion, seven hundred twenty-one billion, eight hundred fifty-six million, five hundred sixty-five thousand, six hundred forty-eight".