173778989 has 2 divisors, whose sum is σ = 173778990. Its totient is φ = 173778988.

The previous prime is 173778977. The next prime is 173779003. The reversal of 173778989 is 989877371.

173778989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107226025 + 66552964 = 10355^2 + 8158^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-173778989 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (173778929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86889494 + 86889495.

It is an arithmetic number, because the mean of its divisors is an integer number (86889495).

Almost surely, 2^173778989 is an apocalyptic number.

It is an amenable number.

173778989 is a deficient number, since it is larger than the sum of its proper divisors (1).

173778989 is an equidigital number, since it uses as much as digits as its factorization.

173778989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5334336, while the sum is 59.

The square root of 173778989 is about 13182.5258960489. The cubic root of 173778989 is about 558.0405465927.

The spelling of 173778989 in words is "one hundred seventy-three million, seven hundred seventy-eight thousand, nine hundred eighty-nine".