78147889 has 2 divisors, whose sum is σ = 78147890. Its totient is φ = 78147888.

The previous prime is 78147871. The next prime is 78147907. The reversal of 78147889 is 98874187.

It is a balanced prime because it is at equal distance from previous prime (78147871) and next prime (78147907).

It can be written as a sum of positive squares in only one way, i.e., 52056225 + 26091664 = 7215^2 + 5108^2 .

It is a cyclic number.

It is not a de Polignac number, because 78147889 - 2⁷ = 78147761 is a prime.

It is a super-3 number, since 3×78147889³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (78147809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39073944 + 39073945.

It is an arithmetic number, because the mean of its divisors is an integer number (39073945).

Almost surely, 2^78147889 is an apocalyptic number.

It is an amenable number.

78147889 is a deficient number, since it is larger than the sum of its proper divisors (1).

78147889 is an equidigital number, since it uses as much as digits as its factorization.

78147889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 903168, while the sum is 52.

The square root of 78147889 is about 8840.1294673777. The cubic root of 78147889 is about 427.5357315414.

The spelling of 78147889 in words is "seventy-eight million, one hundred forty-seven thousand, eight hundred eighty-nine".