501378538656 has 96 divisors (see below), whose sum is σ = 1323273369600. Its totient is φ = 166218345216.

The previous prime is 501378538649. The next prime is 501378538691. The reversal of 501378538656 is 656835873105.

It is a tau number, because it is divible by the number of its divisors (96).

It is a junction number, because it is equal to n+sod(n) for n = 501378538596 and 501378538605.

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, 71961285 + ... + 71968251.

It is an arithmetic number, because the mean of its divisors is an integer number (13784097600).

Almost surely, 2^501378538656 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 501378538656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (661636684800).

501378538656 is an abundant number, since it is smaller than the sum of its proper divisors (821894830944).

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

501378538656 is a wasteful number, since it uses less digits than its factorization.

501378538656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10946 (or 10938 counting only the distinct ones).

The product of its (nonzero) digits is 18144000, while the sum is 57.

The spelling of 501378538656 in words is "five hundred one billion, three hundred seventy-eight million, five hundred thirty-eight thousand, six hundred fifty-six".