420212621 has 4 divisors (see below), whose sum is σ = 424373244. Its totient is φ = 416052000.

The previous prime is 420212603. The next prime is 420212627. The reversal of 420212621 is 126212024.

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 242923396 + 177289225 = 15586^2 + 13315^2 .

It is a cyclic number.

It is not a de Polignac number, because 420212621 - 2¹⁴ = 420196237 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 420212593 and 420212602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420212627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2080160 + ... + 2080361.

It is an arithmetic number, because the mean of its divisors is an integer number (106093311).

Almost surely, 2^420212621 is an apocalyptic number.

It is an amenable number.

420212621 is a deficient number, since it is larger than the sum of its proper divisors (4160623).

420212621 is a wasteful number, since it uses less digits than its factorization.

420212621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4160622.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 420212621 is about 20499.0882967999. The cubic root of 420212621 is about 749.0135897470.

Adding to 420212621 its reverse (126212024), we get a palindrome (546424645).

The spelling of 420212621 in words is "four hundred twenty million, two hundred twelve thousand, six hundred twenty-one".