122278789 has 2 divisors, whose sum is σ = 122278790. Its totient is φ = 122278788.

The previous prime is 122278777. The next prime is 122278829. The reversal of 122278789 is 987872221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 113529025 + 8749764 = 10655^2 + 2958^2 .

It is a cyclic number.

It is not a de Polignac number, because 122278789 - 2⁵ = 122278757 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (122278589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61139394 + 61139395.

It is an arithmetic number, because the mean of its divisors is an integer number (61139395).

Almost surely, 2^122278789 is an apocalyptic number.

It is an amenable number.

122278789 is a deficient number, since it is larger than the sum of its proper divisors (1).

122278789 is an equidigital number, since it uses as much as digits as its factorization.

122278789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 46.

The square root of 122278789 is about 11057.9740006929. The cubic root of 122278789 is about 496.3450666911.

The spelling of 122278789 in words is "one hundred twenty-two million, two hundred seventy-eight thousand, seven hundred eighty-nine".