21317977976833 has 2 divisors, whose sum is σ = 21317977976834. Its totient is φ = 21317977976832.

The previous prime is 21317977976797. The next prime is 21317977976843. The reversal of 21317977976833 is 33867977971312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12136423485169 + 9181554491664 = 3483737^2 + 3030108^2 .

It is a cyclic number.

It is not a de Polignac number, because 21317977976833 - 2¹³ = 21317977968641 is a prime.

It is not a weakly prime, because it can be changed into another prime (21317977976843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10658988988416 + 10658988988417.

It is an arithmetic number, because the mean of its divisors is an integer number (10658988988417).

Almost surely, 2^{21317977976833} is an apocalyptic number.

It is an amenable number.

21317977976833 is a deficient number, since it is larger than the sum of its proper divisors (1).

21317977976833 is an equidigital number, since it uses as much as digits as its factorization.

21317977976833 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 504094752, while the sum is 73.

The spelling of 21317977976833 in words is "twenty-one trillion, three hundred seventeen billion, nine hundred seventy-seven million, nine hundred seventy-six thousand, eight hundred thirty-three".