78103227821 has 2 divisors, whose sum is σ = 78103227822. Its totient is φ = 78103227820.

The previous prime is 78103227803. The next prime is 78103227871. The reversal of 78103227821 is 12872230187.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59238205321 + 18865022500 = 243389^2 + 137350^2 .

It is a cyclic number.

It is not a de Polignac number, because 78103227821 - 2¹⁰ = 78103226797 is a prime.

It is a super-2 number, since 2×78103227821² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78103227871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39051613910 + 39051613911.

It is an arithmetic number, because the mean of its divisors is an integer number (39051613911).

Almost surely, 2^78103227821 is an apocalyptic number.

It is an amenable number.

78103227821 is a deficient number, since it is larger than the sum of its proper divisors (1).

78103227821 is an equidigital number, since it uses as much as digits as its factorization.

78103227821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 75264, while the sum is 41.

The spelling of 78103227821 in words is "seventy-eight billion, one hundred three million, two hundred twenty-seven thousand, eight hundred twenty-one".