122021209 has 4 divisors (see below), whose sum is σ = 122640804. Its totient is φ = 121401616.

The previous prime is 122021201. The next prime is 122021213. The reversal of 122021209 is 902120221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 902120221 = 2083 ⋅433087.

It can be written as a sum of positive squares in 2 ways, for example, as 52881984 + 69139225 = 7272^2 + 8315^2 .

It is a cyclic number.

It is not a de Polignac number, because 122021209 - 2³ = 122021201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (122021201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309502 + ... + 309895.

It is an arithmetic number, because the mean of its divisors is an integer number (30660201).

Almost surely, 2^122021209 is an apocalyptic number.

It is an amenable number.

122021209 is a deficient number, since it is larger than the sum of its proper divisors (619595).

122021209 is an equidigital number, since it uses as much as digits as its factorization.

122021209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619594.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 122021209 is about 11046.3210617834. The cubic root of 122021209 is about 495.9963050908.

The spelling of 122021209 in words is "one hundred twenty-two million, twenty-one thousand, two hundred nine".