66660087 has 8 divisors (see below), whose sum is σ = 95717104. Its totient is φ = 41021568.

The previous prime is 66660071. The next prime is 66660103. The reversal of 66660087 is 78006666.

It is an interprime number because it is at equal distance from previous prime (66660071) and next prime (66660103).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66660087 - 2⁴ = 66660071 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 1709233 = 66660087 / (6 + 6 + 6 + 6 + 0 + 0 + 8 + 7).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66660487) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 854578 + ... + 854655.

It is an arithmetic number, because the mean of its divisors is an integer number (11964638).

Almost surely, 2^66660087 is an apocalyptic number.

66660087 is a deficient number, since it is larger than the sum of its proper divisors (29057017).

66660087 is a wasteful number, since it uses less digits than its factorization.

66660087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1709249.

The product of its (nonzero) digits is 72576, while the sum is 39.

The square root of 66660087 is about 8164.5628786849. The cubic root of 66660087 is about 405.4667929788.

The spelling of 66660087 in words is "sixty-six million, six hundred sixty thousand, eighty-seven".