20204397 has 10 divisors (see below), whose sum is σ = 30181998. Its totient is φ = 13469544.

The previous prime is 20204389. The next prime is 20204411. The reversal of 20204397 is 79340202.

It can be written as a sum of positive squares in only one way, i.e., 11329956 + 8874441 = 3366^2 + 2979^2 .

It is not a de Polignac number, because 20204397 - 2³ = 20204389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 20204397.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20204357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 124638 + ... + 124799.

Almost surely, 2^20204397 is an apocalyptic number.

20204397 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20204397 is a deficient number, since it is larger than the sum of its proper divisors (9977601).

20204397 is an equidigital number, since it uses as much as digits as its factorization.

20204397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249449 (or 249440 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 20204397 is about 4494.9301440623. The cubic root of 20204397 is about 272.3633273614.

Adding to 20204397 its reverse (79340202), we get a palindrome (99544599).

The spelling of 20204397 in words is "twenty million, two hundred four thousand, three hundred ninety-seven".