20100402221 has 2 divisors, whose sum is σ = 20100402222. Its totient is φ = 20100402220.

The previous prime is 20100402211. The next prime is 20100402229. The reversal of 20100402221 is 12220400102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15653512996 + 4446889225 = 125114^2 + 66685^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20100402221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20100402196 and 20100402205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20100402229) 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 as a sum of consecutive naturals, namely, 10050201110 + 10050201111.

It is an arithmetic number, because the mean of its divisors is an integer number (10050201111).

Almost surely, 2^20100402221 is an apocalyptic number.

It is an amenable number.

20100402221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20100402221 is an equidigital number, since it uses as much as digits as its factorization.

20100402221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 20100402221 its reverse (12220400102), we get a palindrome (32320802323).

The spelling of 20100402221 in words is "twenty billion, one hundred million, four hundred two thousand, two hundred twenty-one".