665970187 has 2 divisors, whose sum is σ = 665970188. Its totient is φ = 665970186.

The previous prime is 665970169. The next prime is 665970203. The reversal of 665970187 is 781079566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665970187 - 2¹¹ = 665968139 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 665970187.

It is not a weakly prime, because it can be changed into another prime (665970127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332985093 + 332985094.

It is an arithmetic number, because the mean of its divisors is an integer number (332985094).

Almost surely, 2^665970187 is an apocalyptic number.

665970187 is a deficient number, since it is larger than the sum of its proper divisors (1).

665970187 is an equidigital number, since it uses as much as digits as its factorization.

665970187 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 49.

The square root of 665970187 is about 25806.3981795213. The cubic root of 665970187 is about 873.2761432194.

The spelling of 665970187 in words is "six hundred sixty-five million, nine hundred seventy thousand, one hundred eighty-seven".