78648461 has 2 divisors, whose sum is σ = 78648462. Its totient is φ = 78648460.

The previous prime is 78648439. The next prime is 78648469. The reversal of 78648461 is 16484687.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75151561 + 3496900 = 8669^2 + 1870^2 .

It is an emirp because it is prime and its reverse (16484687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78648461 - 2¹⁴ = 78632077 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78648469) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39324230 + 39324231.

It is an arithmetic number, because the mean of its divisors is an integer number (39324231).

Almost surely, 2^78648461 is an apocalyptic number.

It is an amenable number.

78648461 is a deficient number, since it is larger than the sum of its proper divisors (1).

78648461 is an equidigital number, since it uses as much as digits as its factorization.

78648461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 258048, while the sum is 44.

The square root of 78648461 is about 8868.3967547692. The cubic root of 78648461 is about 428.4466415688.

It can be divided in two parts, 7 and 8648461, that added together give a palindrome (8648468).

The spelling of 78648461 in words is "seventy-eight million, six hundred forty-eight thousand, four hundred sixty-one".