78028081 has 2 divisors, whose sum is σ = 78028082. Its totient is φ = 78028080.

The previous prime is 78028073. The next prime is 78028087. The reversal of 78028081 is 18082087.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77880625 + 147456 = 8825^2 + 384^2 .

It is an emirp because it is prime and its reverse (18082087) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78028081 - 2³ = 78028073 is a prime.

It is a super-2 number, since 2×78028081² = 12176762849085122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78028087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39014040 + 39014041.

It is an arithmetic number, because the mean of its divisors is an integer number (39014041).

Almost surely, 2^78028081 is an apocalyptic number.

It is an amenable number.

78028081 is a deficient number, since it is larger than the sum of its proper divisors (1).

78028081 is an equidigital number, since it uses as much as digits as its factorization.

78028081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7168, while the sum is 34.

The square root of 78028081 is about 8833.3504968387. The cubic root of 78028081 is about 427.3171357481.

The spelling of 78028081 in words is "seventy-eight million, twenty-eight thousand, eighty-one".