20405240411 has 4 divisors (see below), whose sum is σ = 20442544872. Its totient is φ = 20367935952.

The previous prime is 20405240407. The next prime is 20405240417. The reversal of 20405240411 is 11404250402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20405240411 - 2² = 20405240407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20405240417) 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, 18651410 + ... + 18652503.

It is an arithmetic number, because the mean of its divisors is an integer number (5110636218).

Almost surely, 2^20405240411 is an apocalyptic number.

20405240411 is a deficient number, since it is larger than the sum of its proper divisors (37304461).

20405240411 is an equidigital number, since it uses as much as digits as its factorization.

20405240411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37304460.

The product of its (nonzero) digits is 1280, while the sum is 23.

Adding to 20405240411 its reverse (11404250402), we get a palindrome (31809490813).

Subtracting from 20405240411 its reverse (11404250402), we obtain a palindrome (9000990009).

The spelling of 20405240411 in words is "twenty billion, four hundred five million, two hundred forty thousand, four hundred eleven".