20506913280 has 480 divisors, whose sum is σ = 83082789504. Its totient is φ = 4576739328.

The previous prime is 20506913279. The next prime is 20506913291. The reversal of 20506913280 is 8231960502.

It is a tau number, because it is divible by the number of its divisors (480).

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

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 6933562 + ... + 6936518.

Almost surely, 2^20506913280 is an apocalyptic number.

20506913280 is a gapful number since it is divisible by the number (20) 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 20506913280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41541394752).

20506913280 is an abundant number, since it is smaller than the sum of its proper divisors (62575876224).

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

20506913280 is a wasteful number, since it uses less digits than its factorization.

20506913280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3036 (or 3017 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 20506913280 in words is "twenty billion, five hundred six million, nine hundred thirteen thousand, two hundred eighty".