667724669 has 4 divisors (see below), whose sum is σ = 676176960. Its totient is φ = 659272380.

The previous prime is 667724627. The next prime is 667724671. The reversal of 667724669 is 966427766.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 667724669 - 2¹⁶ = 667659133 is a prime.

It is a super-2 number, since 2×667724669² = 891712467182319122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 667724669.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667724689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4226027 + ... + 4226184.

It is an arithmetic number, because the mean of its divisors is an integer number (169044240).

Almost surely, 2^667724669 is an apocalyptic number.

It is an amenable number.

667724669 is a deficient number, since it is larger than the sum of its proper divisors (8452291).

667724669 is an equidigital number, since it uses as much as digits as its factorization.

667724669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8452290.

The product of its digits is 4572288, while the sum is 53.

The square root of 667724669 is about 25840.3689795637. The cubic root of 667724669 is about 874.0423455719.

The spelling of 667724669 in words is "six hundred sixty-seven million, seven hundred twenty-four thousand, six hundred sixty-nine".