77833881364721 has 2 divisors, whose sum is σ = 77833881364722. Its totient is φ = 77833881364720.

The previous prime is 77833881364669. The next prime is 77833881364769. The reversal of 77833881364721 is 12746318833877.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55436378604721 + 22397502760000 = 7445561^2 + 4732600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77833881364721 is a prime.

It is a super-2 number, since 2×77833881364721² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (77833881367721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38916940682360 + 38916940682361.

It is an arithmetic number, because the mean of its divisors is an integer number (38916940682361).

Almost surely, 2^{77833881364721} is an apocalyptic number.

It is an amenable number.

77833881364721 is a deficient number, since it is larger than the sum of its proper divisors (1).

77833881364721 is an equidigital number, since it uses as much as digits as its factorization.

77833881364721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 227598336, while the sum is 68.

The spelling of 77833881364721 in words is "seventy-seven trillion, eight hundred thirty-three billion, eight hundred eighty-one million, three hundred sixty-four thousand, seven hundred twenty-one".