66315478 has 4 divisors (see below), whose sum is σ = 99473220. Its totient is φ = 33157738.

The previous prime is 66315443. The next prime is 66315481. The reversal of 66315478 is 87451366.

It is a happy number.

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

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 66315478.

It is a congruent number.

It is an unprimeable number.

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, 16578868 + ... + 16578871.

It is an arithmetic number, because the mean of its divisors is an integer number (24868305).

Almost surely, 2^66315478 is an apocalyptic number.

66315478 is a deficient number, since it is larger than the sum of its proper divisors (33157742).

66315478 is a wasteful number, since it uses less digits than its factorization.

66315478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33157741.

The product of its digits is 120960, while the sum is 40.

The square root of 66315478 is about 8143.4315862540. The cubic root of 66315478 is about 404.7668789981.

The spelling of 66315478 in words is "sixty-six million, three hundred fifteen thousand, four hundred seventy-eight".