20013721565628 has 192 divisors, whose sum is σ = 56266779340800. Its totient is φ = 5408778447360.

The previous prime is 20013721565627. The next prime is 20013721565633. The reversal of 20013721565628 is 82656512731002.

It is a super-2 number, since 2×20013721565628² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20013721565627) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3329513143 + ... + 3329519153.

It is an arithmetic number, because the mean of its divisors is an integer number (293056142400).

Almost surely, 2^{20013721565628} is an apocalyptic number.

20013721565628 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20013721565628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28133389670400).

20013721565628 is an abundant number, since it is smaller than the sum of its proper divisors (36253057775172).

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

20013721565628 is a wasteful number, since it uses less digits than its factorization.

20013721565628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8960 (or 8958 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 48.

The spelling of 20013721565628 in words is "twenty trillion, thirteen billion, seven hundred twenty-one million, five hundred sixty-five thousand, six hundred twenty-eight".