20686243228 has 96 divisors (see below), whose sum is σ = 44351193600. Its totient is φ = 8254960896.

The previous prime is 20686243223. The next prime is 20686243247. The reversal of 20686243228 is 82234268602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20686243223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2535051 + ... + 2543197.

It is an arithmetic number, because the mean of its divisors is an integer number (461991600).

Almost surely, 2^20686243228 is an apocalyptic number.

20686243228 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 20686243228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22175596800).

20686243228 is an abundant number, since it is smaller than the sum of its proper divisors (23664950372).

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

20686243228 is a wasteful number, since it uses less digits than its factorization.

20686243228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8299 (or 8297 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 43.

The spelling of 20686243228 in words is "twenty billion, six hundred eighty-six million, two hundred forty-three thousand, two hundred twenty-eight".