78661413 has 6 divisors (see below), whose sum is σ = 113622054. Its totient is φ = 52440936.

The previous prime is 78661399. The next prime is 78661481. The reversal of 78661413 is 31416687.

It can be written as a sum of positive squares in only one way, i.e., 61496964 + 17164449 = 7842^2 + 4143^2 .

It is not a de Polignac number, because 78661413 - 2¹³ = 78653221 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78661213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4370070 + ... + 4370087.

It is an arithmetic number, because the mean of its divisors is an integer number (18937009).

Almost surely, 2^78661413 is an apocalyptic number.

It is an amenable number.

78661413 is a deficient number, since it is larger than the sum of its proper divisors (34960641).

78661413 is a wasteful number, since it uses less digits than its factorization.

78661413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8740163 (or 8740160 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 78661413 is about 8869.1269581622. The cubic root of 78661413 is about 428.4701594535.

The spelling of 78661413 in words is "seventy-eight million, six hundred sixty-one thousand, four hundred thirteen".