78561337 has 2 divisors, whose sum is σ = 78561338. Its totient is φ = 78561336.

The previous prime is 78561331. The next prime is 78561361. The reversal of 78561337 is 73316587.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62473216 + 16088121 = 7904^2 + 4011^2 .

It is an emirp because it is prime and its reverse (73316587) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78561337 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78561337.

It is not a weakly prime, because it can be changed into another prime (78561331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39280668 + 39280669.

It is an arithmetic number, because the mean of its divisors is an integer number (39280669).

Almost surely, 2^78561337 is an apocalyptic number.

It is an amenable number.

78561337 is a deficient number, since it is larger than the sum of its proper divisors (1).

78561337 is an equidigital number, since it uses as much as digits as its factorization.

78561337 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 40.

The square root of 78561337 is about 8863.4833445999. The cubic root of 78561337 is about 428.2883770723.

The spelling of 78561337 in words is "seventy-eight million, five hundred sixty-one thousand, three hundred thirty-seven".