10221021 has 12 divisors (see below), whose sum is σ = 15273180. Its totient is φ = 6578880.

The previous prime is 10221007. The next prime is 10221037. The reversal of 10221021 is 12012201.

It can be written as a sum of positive squares in 2 ways, for example, as 4995225 + 5225796 = 2235^2 + 2286^2 .

It is not a de Polignac number, because 10221021 - 2¹⁰ = 10219997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 10220994 and 10221012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10221091) 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 11 ways as a sum of consecutive naturals, for example, 19320 + ... + 19841.

It is an arithmetic number, because the mean of its divisors is an integer number (1272765).

Almost surely, 2^10221021 is an apocalyptic number.

It is an amenable number.

10221021 is a deficient number, since it is larger than the sum of its proper divisors (5052159).

10221021 is a wasteful number, since it uses less digits than its factorization.

10221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39196 (or 39193 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 10221021 is about 3197.0331559119. The cubic root of 10221021 is about 217.0191676812.

Adding to 10221021 its reverse (12012201), we get a palindrome (22233222).

The spelling of 10221021 in words is "ten million, two hundred twenty-one thousand, twenty-one".