10221220021 has 4 divisors (see below), whose sum is σ = 10224935532. Its totient is φ = 10217504512.

The previous prime is 10221219997. The next prime is 10221220073. The reversal of 10221220021 is 12002212201.

It is a happy number.

10221220021 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4618697521 + 5602522500 = 67961^2 + 74850^2 .

It is a cyclic number.

It is not a de Polignac number, because 10221220021 - 2¹¹ = 10221217973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10221219983 and 10221220010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10221227021) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1853626 + ... + 1859131.

It is an arithmetic number, because the mean of its divisors is an integer number (2556233883).

Almost surely, 2^10221220021 is an apocalyptic number.

It is an amenable number.

10221220021 is a deficient number, since it is larger than the sum of its proper divisors (3715511).

10221220021 is an equidigital number, since it uses as much as digits as its factorization.

10221220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3715510.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 10221220021 its reverse (12002212201), we get a palindrome (22223432222).

The spelling of 10221220021 in words is "ten billion, two hundred twenty-one million, two hundred twenty thousand, twenty-one".