20409297 has 4 divisors (see below), whose sum is σ = 27212400. Its totient is φ = 13606196.

The previous prime is 20409283. The next prime is 20409317. The reversal of 20409297 is 79290402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20409297 - 2⁸ = 20409041 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20409217) 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, 3401547 + ... + 3401552.

It is an arithmetic number, because the mean of its divisors is an integer number (6803100).

Almost surely, 2^20409297 is an apocalyptic number.

It is an amenable number.

20409297 is a deficient number, since it is larger than the sum of its proper divisors (6803103).

20409297 is an equidigital number, since it uses as much as digits as its factorization.

20409297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6803102.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20409297 is about 4517.6649942199. The cubic root of 20409297 is about 273.2809435912.

Adding to 20409297 its reverse (79290402), we get a palindrome (99699699).

It can be divided in two parts, 20409 and 297, that added together give a triangular number (20706 = T₂₀₃).

The spelling of 20409297 in words is "twenty million, four hundred nine thousand, two hundred ninety-seven".