1201309 has 2 divisors, whose sum is σ = 1201310.
Its totient is φ = 1201308.
The previous prime is 1201307. The next prime is 1201327. The reversal of 1201309 is 9031021.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 675684 + 525625 = 822^2 + 725^2
It is an emirp because it is prime and its reverse (9031021) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 1201309 - 21 = 1201307 is a prime.
Together with 1201307, it forms a pair of twin primes.
It is a junction number, because it is equal to n+sod(n) for n = 1201292 and 1201301.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (1201307) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 600654 + 600655.
It is an arithmetic number, because the mean of its divisors is an integer number (600655).
21201309 is an apocalyptic number.
It is an amenable number.
1201309 is a deficient number, since it is larger than the sum of its proper divisors (1).
1201309 is an equidigital number, since it uses as much as digits as its factorization.
1201309 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 54, while the sum is 16.
The square root of 1201309 is about 1096.0424261861.
The cubic root of 1201309 is about 106.3044823233.
It can be divided in two parts, 120 and 1309, that multiplied together give a triangular number (157080 = T560).
The spelling of 1201309 in words is "one million, two hundred one thousand, three hundred nine".