20409353855280 has 320 divisors, whose sum is σ = 75765817344000. Its totient is φ = 5019904171008.

The previous prime is 20409353855273. The next prime is 20409353855347. The reversal of 20409353855280 is 8255835390402.

It is a happy number.

20409353855280 is a `hidden beast` number, since 2 + 0 + 4 + 0 + 9 + 3 + 5 + 3 + 8 + 552 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 35630181 + ... + 36198459.

It is an arithmetic number, because the mean of its divisors is an integer number (236768179200).

Almost surely, 2^{20409353855280} is an apocalyptic number.

20409353855280 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 20409353855280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37882908672000).

20409353855280 is an abundant number, since it is smaller than the sum of its proper divisors (55356463488720).

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

20409353855280 is a wasteful number, since it uses less digits than its factorization.

20409353855280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569593 (or 569581 counting only the distinct ones).

The product of its (nonzero) digits is 10368000, while the sum is 54.

The spelling of 20409353855280 in words is "twenty trillion, four hundred nine billion, three hundred fifty-three million, eight hundred fifty-five thousand, two hundred eighty".