405820011 has 4 divisors (see below), whose sum is σ = 541093352. Its totient is φ = 270546672.

The previous prime is 405819989. The next prime is 405820013. The reversal of 405820011 is 110028504.

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

It is not a de Polignac number, because 405820011 - 2²⁶ = 338711147 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 405820011.

It is not an unprimeable number, because it can be changed into a prime (405820013) 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, 67636666 + ... + 67636671.

It is an arithmetic number, because the mean of its divisors is an integer number (135273338).

Almost surely, 2^405820011 is an apocalyptic number.

405820011 is a deficient number, since it is larger than the sum of its proper divisors (135273341).

405820011 is a wasteful number, since it uses less digits than its factorization.

405820011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135273340.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 405820011 is about 20144.9748324489. The cubic root of 405820011 is about 740.3626241968.

Adding to 405820011 its reverse (110028504), we get a palindrome (515848515).

The spelling of 405820011 in words is "four hundred five million, eight hundred twenty thousand, eleven".