667989509461 has 4 divisors (see below), whose sum is σ = 668900819212. Its totient is φ = 667078199712.

The previous prime is 667989509387. The next prime is 667989509477. The reversal of 667989509461 is 164905989766.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 635695263025 + 32294246436 = 797305^2 + 179706^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667989509461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667989501461) 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, 455653776 + ... + 455655241.

It is an arithmetic number, because the mean of its divisors is an integer number (167225204803).

Almost surely, 2^667989509461 is an apocalyptic number.

It is an amenable number.

667989509461 is a deficient number, since it is larger than the sum of its proper divisors (911309751).

667989509461 is an equidigital number, since it uses as much as digits as its factorization.

667989509461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 911309750.

The product of its (nonzero) digits is 176359680, while the sum is 70.

The spelling of 667989509461 in words is "six hundred sixty-seven billion, nine hundred eighty-nine million, five hundred nine thousand, four hundred sixty-one".