420821421 has 8 divisors (see below), whose sum is σ = 568781760. Its totient is φ = 276704352.

The previous prime is 420821419. The next prime is 420821437. The reversal of 420821421 is 124128024.

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

It is not a de Polignac number, because 420821421 - 2¹ = 420821419 is a prime.

It is a super-4 number, since 4×420821421⁴ (a number of 36 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 420821391 and 420821400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420821441) 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, 960561 + ... + 960998.

It is an arithmetic number, because the mean of its divisors is an integer number (71097720).

Almost surely, 2^420821421 is an apocalyptic number.

It is an amenable number.

420821421 is a deficient number, since it is larger than the sum of its proper divisors (147960339).

420821421 is a wasteful number, since it uses less digits than its factorization.

420821421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1921635.

The product of its (nonzero) digits is 1024, while the sum is 24.

The square root of 420821421 is about 20513.9323631526. The cubic root of 420821421 is about 749.3751364275.

Adding to 420821421 its reverse (124128024), we get a palindrome (544949445).

The spelling of 420821421 in words is "four hundred twenty million, eight hundred twenty-one thousand, four hundred twenty-one".