20439449 has 2 divisors, whose sum is σ = 20439450. Its totient is φ = 20439448.

The previous prime is 20439439. The next prime is 20439481. The reversal of 20439449 is 94493402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16000000 + 4439449 = 4000^2 + 2107^2 .

It is a cyclic number.

It is not a de Polignac number, because 20439449 - 2²⁰ = 19390873 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20439439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10219724 + 10219725.

It is an arithmetic number, because the mean of its divisors is an integer number (10219725).

Almost surely, 2^20439449 is an apocalyptic number.

It is an amenable number.

20439449 is a deficient number, since it is larger than the sum of its proper divisors (1).

20439449 is an equidigital number, since it uses as much as digits as its factorization.

20439449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 20439449 is about 4521.0008847599. Note that the first 3 decimals coincide. The cubic root of 20439449 is about 273.4154560232.

The spelling of 20439449 in words is "twenty million, four hundred thirty-nine thousand, four hundred forty-nine".