21212246677 has 2 divisors, whose sum is σ = 21212246678. Its totient is φ = 21212246676.

The previous prime is 21212246669. The next prime is 21212246719. The reversal of 21212246677 is 77664221212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13982826001 + 7229420676 = 118249^2 + 85026^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212246677 - 2³ = 21212246669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21212246617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606123338 + 10606123339.

It is an arithmetic number, because the mean of its divisors is an integer number (10606123339).

Almost surely, 2^21212246677 is an apocalyptic number.

It is an amenable number.

21212246677 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212246677 is an equidigital number, since it uses as much as digits as its factorization.

21212246677 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 40.

Adding to 21212246677 its reverse (77664221212), we get a palindrome (98876467889).

The spelling of 21212246677 in words is "twenty-one billion, two hundred twelve million, two hundred forty-six thousand, six hundred seventy-seven".