20640546108 has 432 divisors, whose sum is σ = 70083127296. Its totient is φ = 4981927680.

The previous prime is 20640546097. The next prime is 20640546119. The reversal of 20640546108 is 80164504602.

20640546108 is a `hidden beast` number, since 2 + 0 + 6 + 4 + 0 + 546 + 108 = 666.

It is an interprime number because it is at equal distance from previous prime (20640546097) and next prime (20640546119).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 36661435 + ... + 36661997.

Almost surely, 2^20640546108 is an apocalyptic number.

20640546108 is a gapful number since it is divisible by the number (28) 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 20640546108, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35041563648).

20640546108 is an abundant number, since it is smaller than the sum of its proper divisors (49442581188).

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

20640546108 is a wasteful number, since it uses less digits than its factorization.

20640546108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 20640546108 in words is "twenty billion, six hundred forty million, five hundred forty-six thousand, one hundred eight".