665938226 has 4 divisors (see below), whose sum is σ = 998907342. Its totient is φ = 332969112.

The previous prime is 665938123. The next prime is 665938241. The reversal of 665938226 is 622839566.

665938226 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 622839566 = 2 ⋅311419783.

It can be written as a sum of positive squares in only one way, i.e., 506295001 + 159643225 = 22501^2 + 12635^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166484555 + ... + 166484558.

Almost surely, 2^665938226 is an apocalyptic number.

665938226 is a deficient number, since it is larger than the sum of its proper divisors (332969116).

665938226 is a wasteful number, since it uses less digits than its factorization.

665938226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332969115.

The product of its digits is 933120, while the sum is 47.

The square root of 665938226 is about 25805.7789264343. The cubic root of 665938226 is about 873.2621730118.

The spelling of 665938226 in words is "six hundred sixty-five million, nine hundred thirty-eight thousand, two hundred twenty-six".