20405685084 has 12 divisors (see below), whose sum is σ = 47613265224. Its totient is φ = 6801895024.

The previous prime is 20405684983. The next prime is 20405685103. The reversal of 20405685084 is 48058650402.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 850236867 + ... + 850236890.

It is an arithmetic number, because the mean of its divisors is an integer number (3967772102).

Almost surely, 2^20405685084 is an apocalyptic number.

It is an amenable number.

20405685084 is an abundant number, since it is smaller than the sum of its proper divisors (27207580140).

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

20405685084 is a wasteful number, since it uses less digits than its factorization.

20405685084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1700473764 (or 1700473762 counting only the distinct ones).

The product of its (nonzero) digits is 307200, while the sum is 42.

The spelling of 20405685084 in words is "twenty billion, four hundred five million, six hundred eighty-five thousand, eighty-four".