20209950720 has 336 divisors, whose sum is σ = 71111132352. Its totient is φ = 5308416000.

The previous prime is 20209950701. The next prime is 20209950763. The reversal of 20209950720 is 2705990202.

20209950720 is a `hidden beast` number, since 20 + 20 + 99 + 507 + 20 = 666.

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 polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26910345 + ... + 26911095.

Almost surely, 2^20209950720 is an apocalyptic number.

20209950720 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 20209950720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35555566176).

20209950720 is an abundant number, since it is smaller than the sum of its proper divisors (50901181632).

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

20209950720 is an equidigital number, since it uses as much as digits as its factorization.

20209950720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 861 (or 834 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The spelling of 20209950720 in words is "twenty billion, two hundred nine million, nine hundred fifty thousand, seven hundred twenty".