20421326016 has 560 divisors, whose sum is σ = 75652847424. Its totient is φ = 5303107584.

The previous prime is 20421326011. The next prime is 20421326017. The reversal of 20421326016 is 61062312402.

20421326016 is a `hidden beast` number, since 2 + 0 + 4 + 21 + 32 + 601 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421326011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 34437016 + ... + 34437608.

Almost surely, 2^20421326016 is an apocalyptic number.

20421326016 is a gapful number since it is divisible by the number (26) 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 20421326016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37826423712).

20421326016 is an abundant number, since it is smaller than the sum of its proper divisors (55231521408).

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

20421326016 is a wasteful number, since it uses less digits than its factorization.

20421326016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 710 (or 691 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

Adding to 20421326016 its reverse (61062312402), we get a palindrome (81483638418).

The spelling of 20421326016 in words is "twenty billion, four hundred twenty-one million, three hundred twenty-six thousand, sixteen".