21220100051 has 2 divisors, whose sum is σ = 21220100052. Its totient is φ = 21220100050.

The previous prime is 21220100039. The next prime is 21220100123. The reversal of 21220100051 is 15000102212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21220100051 - 2⁶ = 21220099987 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21220099999 and 21220100035.

It is not a weakly prime, because it can be changed into another prime (21220100021) 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, 10610050025 + 10610050026.

It is an arithmetic number, because the mean of its divisors is an integer number (10610050026).

Almost surely, 2^21220100051 is an apocalyptic number.

21220100051 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220100051 is an equidigital number, since it uses as much as digits as its factorization.

21220100051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40, while the sum is 14.

Adding to 21220100051 its reverse (15000102212), we get a palindrome (36220202263).

The spelling of 21220100051 in words is "twenty-one billion, two hundred twenty million, one hundred thousand, fifty-one".