20121308928 has 288 divisors, whose sum is σ = 68380139520. Its totient is φ = 5717053440.

The previous prime is 20121308899. The next prime is 20121308941. The reversal of 20121308928 is 82980312102.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 20121308892 and 20121308901.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9530593 + ... + 9532703.

It is an arithmetic number, because the mean of its divisors is an integer number (237431040).

Almost surely, 2^20121308928 is an apocalyptic number.

20121308928 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 20121308928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34190069760).

20121308928 is an abundant number, since it is smaller than the sum of its proper divisors (48258830592).

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

20121308928 is a wasteful number, since it uses less digits than its factorization.

20121308928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2340 (or 2320 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The spelling of 20121308928 in words is "twenty billion, one hundred twenty-one million, three hundred eight thousand, nine hundred twenty-eight".