83778109 has 2 divisors, whose sum is σ = 83778110. Its totient is φ = 83778108.

The previous prime is 83778077. The next prime is 83778119. The reversal of 83778109 is 90187738.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43099225 + 40678884 = 6565^2 + 6378^2 .

It is a cyclic number.

It is not a de Polignac number, because 83778109 - 2⁵ = 83778077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (83778119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41889054 + 41889055.

It is an arithmetic number, because the mean of its divisors is an integer number (41889055).

Almost surely, 2^83778109 is an apocalyptic number.

It is an amenable number.

83778109 is a deficient number, since it is larger than the sum of its proper divisors (1).

83778109 is an equidigital number, since it uses as much as digits as its factorization.

83778109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 83778109 is about 9153.0382387489. The cubic root of 83778109 is about 437.5659485890.

The spelling of 83778109 in words is "eighty-three million, seven hundred seventy-eight thousand, one hundred nine".