1222021100021 has 2 divisors, whose sum is σ = 1222021100022. Its totient is φ = 1222021100020.

The previous prime is 1222021099997. The next prime is 1222021100033. The reversal of 1222021100021 is 1200011202221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1146676888900 + 75344211121 = 1070830^2 + 274489^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1222021100021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1222021099969 and 1222021100005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1222021180021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 611010550010 + 611010550011.

It is an arithmetic number, because the mean of its divisors is an integer number (611010550011).

Almost surely, 2^{1222021100021} is an apocalyptic number.

It is an amenable number.

1222021100021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1222021100021 is an equidigital number, since it uses as much as digits as its factorization.

1222021100021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 1222021100021 its reverse (1200011202221), we get a palindrome (2422032302242).

The spelling of 1222021100021 in words is "one trillion, two hundred twenty-two billion, twenty-one million, one hundred thousand, twenty-one".