20806455860 has 12 divisors (see below), whose sum is σ = 43693557348. Its totient is φ = 8322582336.

The previous prime is 20806455827. The next prime is 20806455869. The reversal of 20806455860 is 6855460802.

It can be written as a sum of positive squares in 2 ways, for example, as 5524056976 + 15282398884 = 74324^2 + 123622^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20806455869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 520161377 + ... + 520161416.

It is an arithmetic number, because the mean of its divisors is an integer number (3641129779).

Almost surely, 2^20806455860 is an apocalyptic number.

20806455860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20806455860 is an abundant number, since it is smaller than the sum of its proper divisors (22887101488).

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

20806455860 is a wasteful number, since it uses less digits than its factorization.

20806455860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1040322802 (or 1040322800 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 44.

The spelling of 20806455860 in words is "twenty billion, eight hundred six million, four hundred fifty-five thousand, eight hundred sixty".