20732420856 has 256 divisors, whose sum is σ = 66120883200. Its totient is φ = 5280178176.

The previous prime is 20732420833. The next prime is 20732420857. The reversal of 20732420856 is 65802423702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20732420857) 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, 4387311 + ... + 4392033.

It is an arithmetic number, because the mean of its divisors is an integer number (258284700).

Almost surely, 2^20732420856 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 20732420856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33060441600).

20732420856 is an abundant number, since it is smaller than the sum of its proper divisors (45388462344).

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

20732420856 is a wasteful number, since it uses less digits than its factorization.

20732420856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4838 (or 4834 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 39.

The spelling of 20732420856 in words is "twenty billion, seven hundred thirty-two million, four hundred twenty thousand, eight hundred fifty-six".