20005407 has 32 divisors (see below), whose sum is σ = 30643200. Its totient is φ = 12894336.

The previous prime is 20005397. The next prime is 20005429. The reversal of 20005407 is 70450002.

It is a happy number.

It is not a de Polignac number, because 20005407 - 2⁶ = 20005343 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20005407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20005207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 176983 + ... + 177095.

It is an arithmetic number, because the mean of its divisors is an integer number (957600).

Almost surely, 2^20005407 is an apocalyptic number.

20005407 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

20005407 is a deficient number, since it is larger than the sum of its proper divisors (10637793).

20005407 is a wasteful number, since it uses less digits than its factorization.

20005407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284 (or 278 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 18.

The square root of 20005407 is about 4472.7404351248. The cubic root of 20005407 is about 271.4662208822.

Adding to 20005407 its reverse (70450002), we get a palindrome (90455409).

The spelling of 20005407 in words is "twenty million, five thousand, four hundred seven".