20928417880440 has 128 divisors (see below), whose sum is σ = 72389572162560. Its totient is φ = 4741305268224.

The previous prime is 20928417880319. The next prime is 20928417880441. The reversal of 20928417880440 is 4408871482902.

It is a happy number.

It is a hoax number, since the sum of its digits (57) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20928417880441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 110147484 + ... + 110337323.

It is an arithmetic number, because the mean of its divisors is an integer number (565543532520).

Almost surely, 2^{20928417880440} is an apocalyptic number.

20928417880440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20928417880440 is an abundant number, since it is smaller than the sum of its proper divisors (51461154282120).

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

20928417880440 is a wasteful number, since it uses less digits than its factorization.

20928417880440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220484941 (or 220484937 counting only the distinct ones).

The product of its (nonzero) digits is 8257536, while the sum is 57.

The spelling of 20928417880440 in words is "twenty trillion, nine hundred twenty-eight billion, four hundred seventeen million, eight hundred eighty thousand, four hundred forty".