71278789 has 2 divisors, whose sum is σ = 71278790. Its totient is φ = 71278788.

The previous prime is 71278699. The next prime is 71278793. The reversal of 71278789 is 98787217.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63760225 + 7518564 = 7985^2 + 2742^2 .

It is a cyclic number.

It is not a de Polignac number, because 71278789 - 2¹³ = 71270597 is a prime.

It is a super-2 number, since 2×71278789² = 10161331522613042, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71278289) 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, 35639394 + 35639395.

It is an arithmetic number, because the mean of its divisors is an integer number (35639395).

Almost surely, 2^71278789 is an apocalyptic number.

It is an amenable number.

71278789 is a deficient number, since it is larger than the sum of its proper divisors (1).

71278789 is an equidigital number, since it uses as much as digits as its factorization.

71278789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 395136, while the sum is 49.

The square root of 71278789 is about 8442.6766490255. The cubic root of 71278789 is about 414.6230457171.

The spelling of 71278789 in words is "seventy-one million, two hundred seventy-eight thousand, seven hundred eighty-nine".