505434021 has 32 divisors (see below), whose sum is σ = 726681600. Its totient is φ = 311351040.

The previous prime is 505433989. The next prime is 505434031. The reversal of 505434021 is 120434505.

It is not a de Polignac number, because 505434021 - 2⁵ = 505433989 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 505433982 and 505434000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505434031) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1333410 + ... + 1333788.

It is an arithmetic number, because the mean of its divisors is an integer number (22708800).

Almost surely, 2^505434021 is an apocalyptic number.

505434021 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

505434021 is a deficient number, since it is larger than the sum of its proper divisors (221247579).

505434021 is a wasteful number, since it uses less digits than its factorization.

505434021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 809.

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 505434021 is about 22481.8598207533. The cubic root of 505434021 is about 796.5654955956.

Adding to 505434021 its reverse (120434505), we get a palindrome (625868526).

The spelling of 505434021 in words is "five hundred five million, four hundred thirty-four thousand, twenty-one".