4920021 has 28 divisors (see below), whose sum is σ = 7830252. Its totient is φ = 3079296.

The previous prime is 4919989. The next prime is 4920023. The reversal of 4920021 is 1200294.

It can be written as a sum of positive squares in 2 ways, for example, as 3572100 + 1347921 = 1890^2 + 1161^2 .

It is not a de Polignac number, because 4920021 - 2⁵ = 4919989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 4919976 and 4920003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4920023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 12195 + ... + 12591.

Almost surely, 2^4920021 is an apocalyptic number.

It is an amenable number.

4920021 is a deficient number, since it is larger than the sum of its proper divisors (2910231).

4920021 is an equidigital number, since it uses as much as digits as its factorization.

4920021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 417 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 4920021 is about 2218.1120350424. The cubic root of 4920021 is about 170.0809418473.

The spelling of 4920021 in words is "four million, nine hundred twenty thousand, twenty-one".