409342281019681 has 9 divisors (see below), whose sum is σ = 409749940391673. Its totient is φ = 408935026884720.

The previous prime is 409342281019631. The next prime is 409342281019709. The reversal of 409342281019681 is 186910182243904.

The square root of 409342281019681 is 20232209.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 240862919418081 + 168479361601600 = 15519759^2 + 12979960^2 .

It is not a de Polignac number, because 409342281019681 - 2²⁷ = 409342146801953 is a prime.

It is a super-2 number, since 2×409342281019681² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (409342281019631) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 21466364215 + ... + 21466383283.

Almost surely, 2^{409342281019681} is an apocalyptic number.

409342281019681 is the 20232209-th square number.

409342281019681 is the 10116105-th centered octagonal number.

It is an amenable number.

409342281019681 is a deficient number, since it is larger than the sum of its proper divisors (407659371992).

409342281019681 is an frugal number, since it uses more digits than its factorization.

409342281019681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40260 (or 20130 counting only the distinct ones).

The product of its (nonzero) digits is 5971968, while the sum is 58.

The spelling of 409342281019681 in words is "four hundred nine trillion, three hundred forty-two billion, two hundred eighty-one million, nineteen thousand, six hundred eighty-one".