421044021 has 32 divisors (see below), whose sum is σ = 638570240. Its totient is φ = 274104000.

The previous prime is 421044017. The next prime is 421044023. The reversal of 421044021 is 120440124.

It is not a de Polignac number, because 421044021 - 2² = 421044017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 421043985 and 421044003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421044023) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 247851 + ... + 249543.

It is an arithmetic number, because the mean of its divisors is an integer number (19955320).

Almost surely, 2^421044021 is an apocalyptic number.

It is an amenable number.

421044021 is a deficient number, since it is larger than the sum of its proper divisors (217526219).

421044021 is a wasteful number, since it uses less digits than its factorization.

421044021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1914 (or 1908 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 421044021 is about 20519.3572267749. The cubic root of 421044021 is about 749.5072443267.

Adding to 421044021 its reverse (120440124), we get a palindrome (541484145).

The spelling of 421044021 in words is "four hundred twenty-one million, forty-four thousand, twenty-one".