409667681 has 8 divisors (see below), whose sum is σ = 418545984. Its totient is φ = 400870800.

The previous prime is 409667669. The next prime is 409667701. The reversal of 409667681 is 186766904.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 409667681 - 2²² = 405473377 is a prime.

It is a super-3 number, since 3×409667681³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (409667281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10130 + ... + 30363.

It is an arithmetic number, because the mean of its divisors is an integer number (52318248).

Almost surely, 2^409667681 is an apocalyptic number.

It is an amenable number.

409667681 is a deficient number, since it is larger than the sum of its proper divisors (8878303).

409667681 is a wasteful number, since it uses less digits than its factorization.

409667681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40711.

The product of its (nonzero) digits is 435456, while the sum is 47.

The square root of 409667681 is about 20240.2490350292. The cubic root of 409667681 is about 742.6951157312.

The spelling of 409667681 in words is "four hundred nine million, six hundred sixty-seven thousand, six hundred eighty-one".