20908128780 has 192 divisors, whose sum is σ = 81098357760. Its totient is φ = 4344537600.

The previous prime is 20908128737. The next prime is 20908128799. The reversal of 20908128780 is 8782180902.

It is a happy number.

It is a super-3 number, since 3×20908128780³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 209841 + ... + 293000.

It is an arithmetic number, because the mean of its divisors is an integer number (422387280).

Almost surely, 2^20908128780 is an apocalyptic number.

20908128780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20908128780 is an abundant number, since it is smaller than the sum of its proper divisors (60190228980).

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

20908128780 is a wasteful number, since it uses less digits than its factorization.

20908128780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502877 (or 502869 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The spelling of 20908128780 in words is "twenty billion, nine hundred eight million, one hundred twenty-eight thousand, seven hundred eighty".