20221909920 has 144 divisors (see below), whose sum is σ = 70138838952. Its totient is φ = 5304084480.

The previous prime is 20221909913. The next prime is 20221909937. The reversal of 20221909920 is 2990912202.

It can be written as a sum of positive squares in 4 ways, for example, as 12313009296 + 7908900624 = 110964^2 + 88932^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27267 + ... + 202946.

Almost surely, 2^20221909920 is an apocalyptic number.

20221909920 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 20221909920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35069419476).

20221909920 is an abundant number, since it is smaller than the sum of its proper divisors (49916929032).

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

20221909920 is a wasteful number, since it uses less digits than its factorization.

20221909920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230295 (or 230284 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The spelling of 20221909920 in words is "twenty billion, two hundred twenty-one million, nine hundred nine thousand, nine hundred twenty".