20636650240 has 72 divisors (see below), whose sum is σ = 49680237600. Its totient is φ = 8213078016.

The previous prime is 20636650219. The next prime is 20636650261. The reversal of 20636650240 is 4205663602.

It is an interprime number because it is at equal distance from previous prime (20636650219) and next prime (20636650261).

It is a junction number, because it is equal to n+sod(n) for n = 20636650196 and 20636650205.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 214212 + ... + 295228.

It is an arithmetic number, because the mean of its divisors is an integer number (690003300).

Almost surely, 2^20636650240 is an apocalyptic number.

20636650240 is a gapful number since it is divisible by the number (20) 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 20636650240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24840118800).

20636650240 is an abundant number, since it is smaller than the sum of its proper divisors (29043587360).

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

20636650240 is an equidigital number, since it uses as much as digits as its factorization.

20636650240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81237 (or 81223 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 34.

The spelling of 20636650240 in words is "twenty billion, six hundred thirty-six million, six hundred fifty thousand, two hundred forty".