1005649 has 4 divisors (see below), whose sum is σ = 1011636.
Its totient is φ = 999664.
The previous prime is 1005647. The next prime is 1005661. The reversal of 1005649 is 9465001.
1005649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
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 819025 + 186624 = 905^2 + 432^2
It is a cyclic number.
It is not a de Polignac number, because 1005649 - 21 = 1005647 is a prime.
It is a super-2 number, since 2×10056492 = 2022659822402, which contains 22 as substring.
It is an Ulam number.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (1005643) 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, 2734 + ... + 3079.
It is an arithmetic number, because the mean of its divisors is an integer number (252909).
It is a 168-hyperperfect number.
21005649 is an apocalyptic number.
It is an amenable number.
1005649 is a deficient number, since it is larger than the sum of its proper divisors (5987).
1005649 is an equidigital number, since it uses as much as digits as its factorization.
1005649 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 5986.
The product of its (nonzero) digits is 1080, while the sum is 25.
The square root of 1005649 is about 1002.8205223269.
The cubic root of 1005649 is about 100.1879465397.
The spelling of 1005649 in words is "one million, five thousand, six hundred forty-nine".