66315715 has 4 divisors (see below), whose sum is σ = 79578864. Its totient is φ = 53052568.

The previous prime is 66315707. The next prime is 66315751. The reversal of 66315715 is 51751366.

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

It is a cyclic number.

It is not a de Polignac number, because 66315715 - 2³ = 66315707 is a prime.

It is a super-2 number, since 2×66315715² = 8795548111922450, which contains 22 as substring.

It is a Duffinian 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 in 3 ways as a sum of consecutive naturals, for example, 6631567 + ... + 6631576.

It is an arithmetic number, because the mean of its divisors is an integer number (19894716).

Almost surely, 2^66315715 is an apocalyptic number.

66315715 is a deficient number, since it is larger than the sum of its proper divisors (13263149).

66315715 is a wasteful number, since it uses less digits than its factorization.

66315715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13263148.

The product of its digits is 18900, while the sum is 34.

The square root of 66315715 is about 8143.4461378461. The cubic root of 66315715 is about 404.7673611864.

The spelling of 66315715 in words is "sixty-six million, three hundred fifteen thousand, seven hundred fifteen".