420321221 has 4 divisors (see below), whose sum is σ = 431681292. Its totient is φ = 408961152.

The previous prime is 420321203. The next prime is 420321247. The reversal of 420321221 is 122123024.

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

It can be written as a sum of positive squares in 2 ways, for example, as 302272996 + 118048225 = 17386^2 + 10865^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420321221 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 420321221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420320221) 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, 5679980 + ... + 5680053.

It is an arithmetic number, because the mean of its divisors is an integer number (107920323).

Almost surely, 2^420321221 is an apocalyptic number.

It is an amenable number.

420321221 is a deficient number, since it is larger than the sum of its proper divisors (11360071).

420321221 is a wasteful number, since it uses less digits than its factorization.

420321221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11360070.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 420321221 is about 20501.7370239695. The cubic root of 420321221 is about 749.0781093619.

Adding to 420321221 its reverse (122123024), we get a palindrome (542444245).

The spelling of 420321221 in words is "four hundred twenty million, three hundred twenty-one thousand, two hundred twenty-one".