421202021 has 8 divisors (see below), whose sum is σ = 424176384. Its totient is φ = 418238640.

The previous prime is 421201997. The next prime is 421202039. The reversal of 421202021 is 120202124.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 421202021 - 2¹⁸ = 420939877 is a prime.

It is a super-2 number, since 2×421202021² = 354822284988968882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 421201987 and 421202005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421202321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83456 + ... + 88358.

It is an arithmetic number, because the mean of its divisors is an integer number (53022048).

Almost surely, 2^421202021 is an apocalyptic number.

It is an amenable number.

421202021 is a deficient number, since it is larger than the sum of its proper divisors (2974363).

421202021 is a wasteful number, since it uses less digits than its factorization.

421202021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5491.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 421202021 is about 20523.2068887881. The cubic root of 421202021 is about 749.6009853837.

Adding to 421202021 its reverse (120202124), we get a palindrome (541404145).

The spelling of 421202021 in words is "four hundred twenty-one million, two hundred two thousand, twenty-one".