78770089 has 2 divisors, whose sum is σ = 78770090. Its totient is φ = 78770088.

The previous prime is 78770063. The next prime is 78770161. The reversal of 78770089 is 98007787.

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., 71571600 + 7198489 = 8460^2 + 2683^2 .

It is a cyclic number.

It is not a de Polignac number, because 78770089 - 2¹⁹ = 78245801 is a prime.

It is not a weakly prime, because it can be changed into another prime (78771089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39385044 + 39385045.

It is an arithmetic number, because the mean of its divisors is an integer number (39385045).

Almost surely, 2^78770089 is an apocalyptic number.

It is an amenable number.

78770089 is a deficient number, since it is larger than the sum of its proper divisors (1).

78770089 is an equidigital number, since it uses as much as digits as its factorization.

78770089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 197568, while the sum is 46.

The square root of 78770089 is about 8875.2514893945. The cubic root of 78770089 is about 428.6673887080.

It can be divided in two parts, 787 and 70089, that added together give a triangular number (70876 = T₃₇₆).

The spelling of 78770089 in words is "seventy-eight million, seven hundred seventy thousand, eighty-nine".