667468681 has 4 divisors (see below), whose sum is σ = 728147664. Its totient is φ = 606789700.

The previous prime is 667468679. The next prime is 667468729. The reversal of 667468681 is 186864766.

It is a happy number.

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 667468681 - 2¹ = 667468679 is a prime.

It is a super-2 number, since 2×667468681² = 891028880231759522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667468621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30339475 + ... + 30339496.

It is an arithmetic number, because the mean of its divisors is an integer number (182036916).

Almost surely, 2^667468681 is an apocalyptic number.

It is an amenable number.

667468681 is a deficient number, since it is larger than the sum of its proper divisors (60678983).

667468681 is a wasteful number, since it uses less digits than its factorization.

667468681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60678982.

The product of its digits is 2322432, while the sum is 52.

The square root of 667468681 is about 25835.4152472918. The cubic root of 667468681 is about 873.9306363795.

The spelling of 667468681 in words is "six hundred sixty-seven million, four hundred sixty-eight thousand, six hundred eighty-one".