21321312201377 has 2 divisors, whose sum is σ = 21321312201378. Its totient is φ = 21321312201376.

The previous prime is 21321312201289. The next prime is 21321312201439. The reversal of 21321312201377 is 77310221312312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21185758634401 + 135553566976 = 4602799^2 + 368176^2 .

It is a cyclic number.

It is not a de Polignac number, because 21321312201377 - 2³⁶ = 21252592724641 is a prime.

It is a super-2 number, since 2×21321312201377² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21321312201677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10660656100688 + 10660656100689.

It is an arithmetic number, because the mean of its divisors is an integer number (10660656100689).

Almost surely, 2^{21321312201377} is an apocalyptic number.

It is an amenable number.

21321312201377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21321312201377 is an equidigital number, since it uses as much as digits as its factorization.

21321312201377 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 35.

Adding to 21321312201377 its reverse (77310221312312), we get a palindrome (98631533513689).

The spelling of 21321312201377 in words is "twenty-one trillion, three hundred twenty-one billion, three hundred twelve million, two hundred one thousand, three hundred seventy-seven".