505400403421 has 4 divisors (see below), whose sum is σ = 511489564992. Its totient is φ = 499311241852.

The previous prime is 505400403397. The next prime is 505400403493. The reversal of 505400403421 is 124304004505.

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 505400403421 - 2¹³ = 505400395229 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 505400403421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505400403821) 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, 3044580661 + ... + 3044580826.

It is an arithmetic number, because the mean of its divisors is an integer number (127872391248).

Almost surely, 2^505400403421 is an apocalyptic number.

It is an amenable number.

505400403421 is a deficient number, since it is larger than the sum of its proper divisors (6089161571).

505400403421 is an equidigital number, since it uses as much as digits as its factorization.

505400403421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6089161570.

The product of its (nonzero) digits is 9600, while the sum is 28.

Adding to 505400403421 its reverse (124304004505), we get a palindrome (629704407926).

The spelling of 505400403421 in words is "five hundred five billion, four hundred million, four hundred three thousand, four hundred twenty-one".