78536641 has 2 divisors, whose sum is σ = 78536642. Its totient is φ = 78536640.

The previous prime is 78536629. The next prime is 78536657. The reversal of 78536641 is 14663587.

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., 65141041 + 13395600 = 8071^2 + 3660^2 .

It is a cyclic number.

It is not a de Polignac number, because 78536641 - 2¹¹ = 78534593 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 78536594 and 78536603.

It is not a weakly prime, because it can be changed into another prime (78506641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39268320 + 39268321.

It is an arithmetic number, because the mean of its divisors is an integer number (39268321).

Almost surely, 2^78536641 is an apocalyptic number.

It is an amenable number.

78536641 is a deficient number, since it is larger than the sum of its proper divisors (1).

78536641 is an equidigital number, since it uses as much as digits as its factorization.

78536641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 40.

The square root of 78536641 is about 8862.0901033560. The cubic root of 78536641 is about 428.2434944424.

The spelling of 78536641 in words is "seventy-eight million, five hundred thirty-six thousand, six hundred forty-one".