501721838542 has 16 divisors (see below), whose sum is σ = 797864893200. Its totient is φ = 235804376448.

The previous prime is 501721838539. The next prime is 501721838543. The reversal of 501721838542 is 245838127105.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 501721838492 and 501721838501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501721838543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9348417 + ... + 9401932.

It is an arithmetic number, because the mean of its divisors is an integer number (49866555825).

Almost surely, 2^501721838542 is an apocalyptic number.

501721838542 is a deficient number, since it is larger than the sum of its proper divisors (296143054658).

501721838542 is a wasteful number, since it uses less digits than its factorization.

501721838542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18751155.

The product of its (nonzero) digits is 537600, while the sum is 46.

The spelling of 501721838542 in words is "five hundred one billion, seven hundred twenty-one million, eight hundred thirty-eight thousand, five hundred forty-two".