409217645 has 4 divisors (see below), whose sum is σ = 491061180. Its totient is φ = 327374112.

The previous prime is 409217629. The next prime is 409217663. The reversal of 409217645 is 546712904.

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 248283049 + 160934596 = 15757^2 + 12686^2 .

It is a cyclic number.

It is not a de Polignac number, because 409217645 - 2⁴ = 409217629 is a prime.

It is a super-3 number, since 3×409217645³ (a number of 27 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 409217599 and 409217608.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40921760 + ... + 40921769.

It is an arithmetic number, because the mean of its divisors is an integer number (122765295).

Almost surely, 2^409217645 is an apocalyptic number.

It is an amenable number.

409217645 is a deficient number, since it is larger than the sum of its proper divisors (81843535).

409217645 is an equidigital number, since it uses as much as digits as its factorization.

409217645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81843534.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 409217645 is about 20229.1286268094. The cubic root of 409217645 is about 742.4230561887.

The spelling of 409217645 in words is "four hundred nine million, two hundred seventeen thousand, six hundred forty-five".