667263505 has 4 divisors (see below), whose sum is σ = 800716212. Its totient is φ = 533810800.

The previous prime is 667263503. The next prime is 667263521. The reversal of 667263505 is 505362766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 505362766 = 2 ⋅252681383.

It can be written as a sum of positive squares in 2 ways, for example, as 488586816 + 178676689 = 22104^2 + 13367^2 .

It is not a de Polignac number, because 667263505 - 2¹ = 667263503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667263503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66726346 + ... + 66726355.

It is an arithmetic number, because the mean of its divisors is an integer number (200179053).

Almost surely, 2^667263505 is an apocalyptic number.

It is an amenable number.

667263505 is a deficient number, since it is larger than the sum of its proper divisors (133452707).

667263505 is a wasteful number, since it uses less digits than its factorization.

667263505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133452706.

The product of its (nonzero) digits is 226800, while the sum is 40.

The square root of 667263505 is about 25831.4441137154. Note that the first 3 decimals coincide. The cubic root of 667263505 is about 873.8410801334.

The spelling of 667263505 in words is "six hundred sixty-seven million, two hundred sixty-three thousand, five hundred five".