3121609 has 2 divisors, whose sum is σ = 3121610. Its totient is φ = 3121608.

The previous prime is 3121603. The next prime is 3121619. The reversal of 3121609 is 9061213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2822400 + 299209 = 1680^2 + 547^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3121609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3121609.

It is not a weakly prime, because it can be changed into another prime (3121603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1560804 + 1560805.

It is an arithmetic number, because the mean of its divisors is an integer number (1560805).

Almost surely, 2^3121609 is an apocalyptic number.

It is an amenable number.

3121609 is a deficient number, since it is larger than the sum of its proper divisors (1).

3121609 is an equidigital number, since it uses as much as digits as its factorization.

3121609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 3121609 is about 1766.8075729971. The cubic root of 3121609 is about 146.1479859359.

The spelling of 3121609 in words is "three million, one hundred twenty-one thousand, six hundred nine".