667500009 has 12 divisors (see below), whose sum is σ = 978265008. Its totient is φ = 404545240.

The previous prime is 667500007. The next prime is 667500037. The reversal of 667500009 is 900005766.

It is not a de Polignac number, because 667500009 - 2¹ = 667500007 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (667500007) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 919059 + ... + 919784.

It is an arithmetic number, because the mean of its divisors is an integer number (81522084).

Almost surely, 2^667500009 is an apocalyptic number.

It is an amenable number.

667500009 is a deficient number, since it is larger than the sum of its proper divisors (310764999).

667500009 is a wasteful number, since it uses less digits than its factorization.

667500009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1838868 (or 1838857 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 33.

The square root of 667500009 is about 25836.0215397031. The cubic root of 667500009 is about 873.9443089664.

It can be divided in two parts, 66 and 7500009, that multiplied together give a palindrome (495000594).

The spelling of 667500009 in words is "six hundred sixty-seven million, five hundred thousand, nine".