20220021090 has 40 divisors (see below), whose sum is σ = 54369392220. Its totient is φ = 5392005408.

The previous prime is 20220021079. The next prime is 20220021091. The reversal of 20220021090 is 9012002202.

It can be written as a sum of positive squares in 2 ways, for example, as 20213161929 + 6859161 = 142173^2 + 2619^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (20220021091) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 12480685 + ... + 12482304.

Almost surely, 2^20220021090 is an apocalyptic number.

20220021090 is an abundant number, since it is smaller than the sum of its proper divisors (34149371130).

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

20220021090 is a wasteful number, since it uses less digits than its factorization.

20220021090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24963008 (or 24962999 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 20220021090 its reverse (9012002202), we get a palindrome (29232023292).

The spelling of 20220021090 in words is "twenty billion, two hundred twenty million, twenty-one thousand, ninety".