20818449 has 6 divisors (see below), whose sum is σ = 30071106. Its totient is φ = 13878960.

The previous prime is 20818409. The next prime is 20818459. The reversal of 20818449 is 94481802.

20818449 is a `hidden beast` number, since 208 + 1 + 8 + 449 = 666.

It can be written as a sum of positive squares in only one way, i.e., 13927824 + 6890625 = 3732^2 + 2625^2 .

It is not a de Polignac number, because 20818449 - 2¹⁷ = 20687377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20818409) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1156572 + ... + 1156589.

It is an arithmetic number, because the mean of its divisors is an integer number (5011851).

Almost surely, 2^20818449 is an apocalyptic number.

It is an amenable number.

20818449 is a deficient number, since it is larger than the sum of its proper divisors (9252657).

20818449 is a wasteful number, since it uses less digits than its factorization.

20818449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2313167 (or 2313164 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 20818449 is about 4562.7238575220. The cubic root of 20818449 is about 275.0950591482.

The spelling of 20818449 in words is "twenty million, eight hundred eighteen thousand, four hundred forty-nine".