121604809 has 2 divisors, whose sum is σ = 121604810. Its totient is φ = 121604808.

The previous prime is 121604789. The next prime is 121604851. The reversal of 121604809 is 908406121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 120231225 + 1373584 = 10965^2 + 1172^2 .

It is a cyclic number.

It is not a de Polignac number, because 121604809 - 2¹³ = 121596617 is a prime.

It is not a weakly prime, because it can be changed into another prime (121604309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60802404 + 60802405.

It is an arithmetic number, because the mean of its divisors is an integer number (60802405).

Almost surely, 2^121604809 is an apocalyptic number.

It is an amenable number.

121604809 is a deficient number, since it is larger than the sum of its proper divisors (1).

121604809 is an equidigital number, since it uses as much as digits as its factorization.

121604809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 121604809 is about 11027.4570504718. The cubic root of 121604809 is about 495.4314627377.

The spelling of 121604809 in words is "one hundred twenty-one million, six hundred four thousand, eight hundred nine".