409617665645 has 4 divisors (see below), whose sum is σ = 491541198780. Its totient is φ = 327694132512.

The previous prime is 409617665591. The next prime is 409617665647. The reversal of 409617665645 is 546566716904.

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 212194737316 + 197422928329 = 460646^2 + 444323^2 .

It is a cyclic number.

It is not a de Polignac number, because 409617665645 - 2¹⁴ = 409617649261 is a prime.

It is a super-3 number, since 3×409617665645³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (409617665647) 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, 40961766560 + ... + 40961766569.

It is an arithmetic number, because the mean of its divisors is an integer number (122885299695).

Almost surely, 2^409617665645 is an apocalyptic number.

It is an amenable number.

409617665645 is a deficient number, since it is larger than the sum of its proper divisors (81923533135).

409617665645 is an equidigital number, since it uses as much as digits as its factorization.

409617665645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81923533134.

The product of its (nonzero) digits is 32659200, while the sum is 59.

The spelling of 409617665645 in words is "four hundred nine billion, six hundred seventeen million, six hundred sixty-five thousand, six hundred forty-five".