2005421123 has 4 divisors (see below), whose sum is σ = 2005537560. Its totient is φ = 2005304688.

The previous prime is 2005421027. The next prime is 2005421149. The reversal of 2005421123 is 3211245002.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2005421123 is a prime.

It is a super-2 number, since 2×2005421123² = 8043427761149162258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2005421095 and 2005421104.

It is not an unprimeable number, because it can be changed into a prime (2005421323) 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, 26693 + ... + 68726.

It is an arithmetic number, because the mean of its divisors is an integer number (501384390).

Almost surely, 2^2005421123 is an apocalyptic number.

2005421123 is a deficient number, since it is larger than the sum of its proper divisors (116437).

2005421123 is an equidigital number, since it uses as much as digits as its factorization.

2005421123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116436.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 2005421123 is about 44781.9285314958. The cubic root of 2005421123 is about 1261.0583874022.

Adding to 2005421123 its reverse (3211245002), we get a palindrome (5216666125).

The spelling of 2005421123 in words is "two billion, five million, four hundred twenty-one thousand, one hundred twenty-three".