21221102221937 has 2 divisors, whose sum is σ = 21221102221938. Its totient is φ = 21221102221936.

The previous prime is 21221102221897. The next prime is 21221102222003. The reversal of 21221102221937 is 73912220112212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21219740907121 + 1361314816 = 4606489^2 + 36896^2 .

It is a cyclic number.

It is not a de Polignac number, because 21221102221937 - 2³² = 21216807254641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21221102221897 and 21221102221906.

It is not a weakly prime, because it can be changed into another prime (21221102221637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610551110968 + 10610551110969.

It is an arithmetic number, because the mean of its divisors is an integer number (10610551110969).

Almost surely, 2^{21221102221937} is an apocalyptic number.

It is an amenable number.

21221102221937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221102221937 is an equidigital number, since it uses as much as digits as its factorization.

21221102221937 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 35.

The spelling of 21221102221937 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred two million, two hundred twenty-one thousand, nine hundred thirty-seven".