78487481 has 2 divisors, whose sum is σ = 78487482. Its totient is φ = 78487480.

The previous prime is 78487463. The next prime is 78487511. The reversal of 78487481 is 18478487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77721856 + 765625 = 8816^2 + 875^2 .

It is an emirp because it is prime and its reverse (18478487) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78487481 - 2⁶ = 78487417 is a prime.

It is a super-2 number, since 2×78487481² = 12320569347450722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (78487411) 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, 39243740 + 39243741.

It is an arithmetic number, because the mean of its divisors is an integer number (39243741).

Almost surely, 2^78487481 is an apocalyptic number.

It is an amenable number.

78487481 is a deficient number, since it is larger than the sum of its proper divisors (1).

78487481 is an equidigital number, since it uses as much as digits as its factorization.

78487481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 401408, while the sum is 47.

The square root of 78487481 is about 8859.3160571231. The cubic root of 78487481 is about 428.1541228062.

The spelling of 78487481 in words is "seventy-eight million, four hundred eighty-seven thousand, four hundred eighty-one".