20404345 has 16 divisors (see below), whose sum is σ = 26933760. Its totient is φ = 14745024.

The previous prime is 20404343. The next prime is 20404361. The reversal of 20404345 is 54340402.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20404345 - 2¹ = 20404343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20404343) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 285 + ... + 6394.

It is an arithmetic number, because the mean of its divisors is an integer number (1683360).

Almost surely, 2^20404345 is an apocalyptic number.

It is an amenable number.

20404345 is a deficient number, since it is larger than the sum of its proper divisors (6529415).

20404345 is a wasteful number, since it uses less digits than its factorization.

20404345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6744.

The product of its (nonzero) digits is 1920, while the sum is 22.

The square root of 20404345 is about 4517.1168902299. The cubic root of 20404345 is about 273.2588393398.

Adding to 20404345 its reverse (54340402), we get a palindrome (74744747).

The spelling of 20404345 in words is "twenty million, four hundred four thousand, three hundred forty-five".