78561187 has 2 divisors, whose sum is σ = 78561188. Its totient is φ = 78561186.

The previous prime is 78561179. The next prime is 78561193. The reversal of 78561187 is 78116587.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78561187 - 2³ = 78561179 is a prime.

It is not a weakly prime, because it can be changed into another prime (78565187) 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, 39280593 + 39280594.

It is an arithmetic number, because the mean of its divisors is an integer number (39280594).

Almost surely, 2^78561187 is an apocalyptic number.

78561187 is a deficient number, since it is larger than the sum of its proper divisors (1).

78561187 is an equidigital number, since it uses as much as digits as its factorization.

78561187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94080, while the sum is 43.

The square root of 78561187 is about 8863.4748829113. The cubic root of 78561187 is about 428.2881044900.

The spelling of 78561187 in words is "seventy-eight million, five hundred sixty-one thousand, one hundred eighty-seven".