10221221021 has 6 divisors (see below), whose sum is σ = 11234895966. Its totient is φ = 9292019000.

The previous prime is 10221220973. The next prime is 10221221027. The reversal of 10221221021 is 12012212201.

10221221021 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 9744453796 + 476767225 = 98714^2 + 21835^2 .

It is not a de Polignac number, because 10221221021 - 2⁶ = 10221220957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10221220987 and 10221221005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10221221027) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 42236330 + ... + 42236571.

It is an arithmetic number, because the mean of its divisors is an integer number (1872482661).

Almost surely, 2^10221221021 is an apocalyptic number.

10221221021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

10221221021 is a deficient number, since it is larger than the sum of its proper divisors (1013674945).

10221221021 is an equidigital number, since it uses as much as digits as its factorization.

10221221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84472923 (or 84472912 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 10221221021 its reverse (12012212201), we get a palindrome (22233433222).

The spelling of 10221221021 in words is "ten billion, two hundred twenty-one million, two hundred twenty-one thousand, twenty-one".