420181 has 4 divisors (see below), whose sum is σ = 434700. Its totient is φ = 405664.

The previous prime is 420163. The next prime is 420191. The reversal of 420181 is 181024.

It is a happy number.

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 133956 + 286225 = 366^2 + 535^2 .

It is a cyclic number.

It is not a de Polignac number, because 420181 - 2⁵ = 420149 is a prime.

It is a super-2 number, since 2×420181² = 353104145522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420191) 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, 7216 + ... + 7273.

It is an arithmetic number, because the mean of its divisors is an integer number (108675).

2⁴²⁰¹⁸¹ is an apocalyptic number.

It is an amenable number.

420181 is a deficient number, since it is larger than the sum of its proper divisors (14519).

420181 is a wasteful number, since it uses less digits than its factorization.

420181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14518.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 420181 is about 648.2136993307. The cubic root of 420181 is about 74.8994801518.

The spelling of 420181 in words is "four hundred twenty thousand, one hundred eighty-one".