1026561 has 4 divisors (see below), whose sum is σ = 1368752. Its totient is φ = 684372.

The previous prime is 1026547. The next prime is 1026563. The reversal of 1026561 is 1656201.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1026561 - 2¹⁰ = 1025537 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1026563) 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, 171091 + ... + 171096.

It is an arithmetic number, because the mean of its divisors is an integer number (342188).

2^1026561 is an apocalyptic number.

It is an amenable number.

1026561 is a deficient number, since it is larger than the sum of its proper divisors (342191).

1026561 is an equidigital number, since it uses as much as digits as its factorization.

1026561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342190.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 1026561 is about 1013.1934662245. The cubic root of 1026561 is about 100.8776415856.

Subtracting from 1026561 its product of nonzero digits (360), we obtain a palindrome (1026201).

The spelling of 1026561 in words is "one million, twenty-six thousand, five hundred sixty-one".