78472417 has 4 divisors (see below), whose sum is σ = 78534036. Its totient is φ = 78410800.

The previous prime is 78472403. The next prime is 78472421. The reversal of 78472417 is 71427487.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 309136 + 78163281 = 556^2 + 8841^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78472417 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78472417.

It is not an unprimeable number, because it can be changed into a prime (78472447) 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 in 3 ways as a sum of consecutive naturals, for example, 28858 + ... + 31459.

It is an arithmetic number, because the mean of its divisors is an integer number (19633509).

Almost surely, 2^78472417 is an apocalyptic number.

It is an amenable number.

78472417 is a deficient number, since it is larger than the sum of its proper divisors (61619).

78472417 is a wasteful number, since it uses less digits than its factorization.

78472417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61618.

The product of its digits is 87808, while the sum is 40.

The square root of 78472417 is about 8858.4658378299. The cubic root of 78472417 is about 428.1267293659.

The spelling of 78472417 in words is "seventy-eight million, four hundred seventy-two thousand, four hundred seventeen".