76665253281821 has 2 divisors, whose sum is σ = 76665253281822. Its totient is φ = 76665253281820.

The previous prime is 76665253281769. The next prime is 76665253281829. The reversal of 76665253281821 is 12818235256667.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57385382198596 + 19279871083225 = 7575314^2 + 4390885^2 .

It is a cyclic number.

It is not a de Polignac number, because 76665253281821 - 2²² = 76665249087517 is a prime.

It is a super-2 number, since 2×76665253281821² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (76665253281829) 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, 38332626640910 + 38332626640911.

It is an arithmetic number, because the mean of its divisors is an integer number (38332626640911).

Almost surely, 2^{76665253281821} is an apocalyptic number.

It is an amenable number.

76665253281821 is a deficient number, since it is larger than the sum of its proper divisors (1).

76665253281821 is an equidigital number, since it uses as much as digits as its factorization.

76665253281821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58060800, while the sum is 62.

The spelling of 76665253281821 in words is "seventy-six trillion, six hundred sixty-five billion, two hundred fifty-three million, two hundred eighty-one thousand, eight hundred twenty-one".