901009 has 2 divisors, whose sum is σ = 901010. Its totient is φ = 901008.

The previous prime is 901007. The next prime is 901013. The reversal of 901009 is 900109.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 760384 + 140625 = 872^2 + 375^2 .

It is a cyclic number.

It is not a de Polignac number, because 901009 - 2¹ = 901007 is a prime.

Together with 901007, it forms a pair of twin primes.

901009 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (901007) by changing a digit.

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 as a sum of consecutive naturals, namely, 450504 + 450505.

It is an arithmetic number, because the mean of its divisors is an integer number (450505).

2⁹⁰¹⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

901009 is a deficient number, since it is larger than the sum of its proper divisors (1).

901009 is an equidigital number, since it uses as much as digits as its factorization.

901009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81, while the sum is 19.

The square root of 901009 is about 949.2149387784. The cubic root of 901009 is about 96.5850056814.

Subtracting from 901009 its reverse (900109), we obtain a square (900 = 30²).

It can be divided in two parts, 90100 and 9, that added together give a palindrome (90109).

The spelling of 901009 in words is "nine hundred one thousand, nine".