21212312320057 has 2 divisors, whose sum is σ = 21212312320058. Its totient is φ = 21212312320056.

The previous prime is 21212312319977. The next prime is 21212312320117. The reversal of 21212312320057 is 75002321321212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17895091207081 + 3317221112976 = 4230259^2 + 1821324^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212312320057 - 2¹¹ = 21212312318009 is a prime.

It is not a weakly prime, because it can be changed into another prime (21212312320757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606156160028 + 10606156160029.

It is an arithmetic number, because the mean of its divisors is an integer number (10606156160029).

Almost surely, 2^{21212312320057} is an apocalyptic number.

It is an amenable number.

21212312320057 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212312320057 is an equidigital number, since it uses as much as digits as its factorization.

21212312320057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 31.

Adding to 21212312320057 its reverse (75002321321212), we get a palindrome (96214633641269).

The spelling of 21212312320057 in words is "twenty-one trillion, two hundred twelve billion, three hundred twelve million, three hundred twenty thousand, fifty-seven".