21211222020077 has 2 divisors, whose sum is σ = 21211222020078. Its totient is φ = 21211222020076.

The previous prime is 21211222020049. The next prime is 21211222020143. The reversal of 21211222020077 is 77002022211212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18145802324521 + 3065419695556 = 4259789^2 + 1750834^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211222020077 - 2⁶ = 21211222020013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21211222029077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605611010038 + 10605611010039.

It is an arithmetic number, because the mean of its divisors is an integer number (10605611010039).

Almost surely, 2^{21211222020077} is an apocalyptic number.

It is an amenable number.

21211222020077 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211222020077 is an equidigital number, since it uses as much as digits as its factorization.

21211222020077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3136, while the sum is 29.

Adding to 21211222020077 its reverse (77002022211212), we get a palindrome (98213244231289).

The spelling of 21211222020077 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty-two million, twenty thousand, seventy-seven".