1201909 has 2 divisors, whose sum is σ = 1201910. Its totient is φ = 1201908.

The previous prime is 1201873. The next prime is 1201919. The reversal of 1201909 is 9091021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 680625 + 521284 = 825^2 + 722^2 .

It is an emirp because it is prime and its reverse (9091021) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1201909 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1201909.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1201919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 600954 + 600955.

It is an arithmetic number, because the mean of its divisors is an integer number (600955).

2^1201909 is an apocalyptic number.

It is an amenable number.

1201909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1201909 is an equidigital number, since it uses as much as digits as its factorization.

1201909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 22.

The square root of 1201909 is about 1096.3161040503. The cubic root of 1201909 is about 106.3221774857.

The spelling of 1201909 in words is "one million, two hundred one thousand, nine hundred nine".