78606961 has 2 divisors, whose sum is σ = 78606962. Its totient is φ = 78606960.

The previous prime is 78606959. The next prime is 78606973. The reversal of 78606961 is 16960687.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78216336 + 390625 = 8844^2 + 625^2 .

It is a cyclic number.

It is not a de Polignac number, because 78606961 - 2¹ = 78606959 is a prime.

Together with 78606959, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (78606161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39303480 + 39303481.

It is an arithmetic number, because the mean of its divisors is an integer number (39303481).

Almost surely, 2^78606961 is an apocalyptic number.

It is an amenable number.

78606961 is a deficient number, since it is larger than the sum of its proper divisors (1).

78606961 is an equidigital number, since it uses as much as digits as its factorization.

78606961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 78606961 is about 8866.0566770126. The cubic root of 78606961 is about 428.3712696175.

The spelling of 78606961 in words is "seventy-eight million, six hundred six thousand, nine hundred sixty-one".