78486553 has 2 divisors, whose sum is σ = 78486554. Its totient is φ = 78486552.

The previous prime is 78486539. The next prime is 78486589. The reversal of 78486553 is 35568487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74597769 + 3888784 = 8637^2 + 1972^2 .

It is an emirp because it is prime and its reverse (35568487) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78486553 - 2⁵ = 78486521 is a prime.

It is not a weakly prime, because it can be changed into another prime (78486593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39243276 + 39243277.

It is an arithmetic number, because the mean of its divisors is an integer number (39243277).

Almost surely, 2^78486553 is an apocalyptic number.

It is an amenable number.

78486553 is a deficient number, since it is larger than the sum of its proper divisors (1).

78486553 is an equidigital number, since it uses as much as digits as its factorization.

78486553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 806400, while the sum is 46.

The square root of 78486553 is about 8859.2636827222. The cubic root of 78486553 is about 428.1524353669.

The spelling of 78486553 in words is "seventy-eight million, four hundred eighty-six thousand, five hundred fifty-three".