78854609 has 2 divisors, whose sum is σ = 78854610. Its totient is φ = 78854608.

The previous prime is 78854599. The next prime is 78854627. The reversal of 78854609 is 90645887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72301009 + 6553600 = 8503^2 + 2560^2 .

It is a cyclic number.

It is not a de Polignac number, because 78854609 - 2⁸ = 78854353 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (78854689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39427304 + 39427305.

It is an arithmetic number, because the mean of its divisors is an integer number (39427305).

Almost surely, 2^78854609 is an apocalyptic number.

It is an amenable number.

78854609 is a deficient number, since it is larger than the sum of its proper divisors (1).

78854609 is an equidigital number, since it uses as much as digits as its factorization.

78854609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 483840, while the sum is 47.

The square root of 78854609 is about 8880.0117680102. The cubic root of 78854609 is about 428.8206533855.

The spelling of 78854609 in words is "seventy-eight million, eight hundred fifty-four thousand, six hundred nine".