20100321221 has 4 divisors (see below), whose sum is σ = 20133436032. Its totient is φ = 20067206412.

The previous prime is 20100321203. The next prime is 20100321239. The reversal of 20100321221 is 12212300102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (20100321203) and next prime (20100321239).

It is a cyclic number.

It is not a de Polignac number, because 20100321221 - 2¹⁰ = 20100320197 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20100321196 and 20100321205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100321271) 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, 16556495 + ... + 16557708.

It is an arithmetic number, because the mean of its divisors is an integer number (5033359008).

Almost surely, 2^20100321221 is an apocalyptic number.

It is an amenable number.

20100321221 is a deficient number, since it is larger than the sum of its proper divisors (33114811).

20100321221 is an equidigital number, since it uses as much as digits as its factorization.

20100321221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33114810.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 20100321221 its reverse (12212300102), we get a palindrome (32312621323).

The spelling of 20100321221 in words is "twenty billion, one hundred million, three hundred twenty-one thousand, two hundred twenty-one".