420550221 has 16 divisors (see below), whose sum is σ = 690134144. Its totient is φ = 221828544.

The previous prime is 420550189. The next prime is 420550241. The reversal of 420550221 is 122055024.

It is a happy number.

It is not a de Polignac number, because 420550221 - 2⁵ = 420550189 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420550241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 769966 + ... + 770511.

It is an arithmetic number, because the mean of its divisors is an integer number (43133384).

Almost surely, 2^420550221 is an apocalyptic number.

It is an amenable number.

420550221 is a deficient number, since it is larger than the sum of its proper divisors (269583923).

420550221 is a wasteful number, since it uses less digits than its factorization.

420550221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1540500.

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 420550221 is about 20507.3211561140. The cubic root of 420550221 is about 749.2141225943.

The spelling of 420550221 in words is "four hundred twenty million, five hundred fifty thousand, two hundred twenty-one".