665372849 has 2 divisors, whose sum is σ = 665372850. Its totient is φ = 665372848.

The previous prime is 665372801. The next prime is 665372857. The reversal of 665372849 is 948273566.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 397723249 + 267649600 = 19943^2 + 16360^2 .

It is a cyclic number.

It is not a de Polignac number, because 665372849 - 2⁸ = 665372593 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 665372797 and 665372806.

It is not a weakly prime, because it can be changed into another prime (665372249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332686424 + 332686425.

It is an arithmetic number, because the mean of its divisors is an integer number (332686425).

Almost surely, 2^665372849 is an apocalyptic number.

It is an amenable number.

665372849 is a deficient number, since it is larger than the sum of its proper divisors (1).

665372849 is an equidigital number, since it uses as much as digits as its factorization.

665372849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 50.

The square root of 665372849 is about 25794.8221354597. The cubic root of 665372849 is about 873.0149718368.

The spelling of 665372849 in words is "six hundred sixty-five million, three hundred seventy-two thousand, eight hundred forty-nine".