20918715280 has 40 divisors (see below), whose sum is σ = 50750626752. Its totient is φ = 8003681664.

The previous prime is 20918715263. The next prime is 20918715281. The reversal of 20918715280 is 8251781902.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (20918715281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5682594 + ... + 5686273.

Almost surely, 2^20918715280 is an apocalyptic number.

20918715280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20918715280 is an abundant number, since it is smaller than the sum of its proper divisors (29831911472).

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

20918715280 is a wasteful number, since it uses less digits than its factorization.

20918715280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11368903 (or 11368897 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 43.

The spelling of 20918715280 in words is "twenty billion, nine hundred eighteen million, seven hundred fifteen thousand, two hundred eighty".