4200921 has 12 divisors (see below), whose sum is σ = 6425172. Its totient is φ = 2635776.

The previous prime is 4200883. The next prime is 4200923. The reversal of 4200921 is 1290024.

It can be written as a sum of positive squares in 2 ways, for example, as 1527696 + 2673225 = 1236^2 + 1635^2 .

It is not a de Polignac number, because 4200921 - 2²¹ = 2103769 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 4200894 and 4200903.

It is not an unprimeable number, because it can be changed into a prime (4200923) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13576 + ... + 13881.

It is an arithmetic number, because the mean of its divisors is an integer number (535431).

Almost surely, 2^4200921 is an apocalyptic number.

It is an amenable number.

4200921 is a deficient number, since it is larger than the sum of its proper divisors (2224251).

4200921 is a wasteful number, since it uses less digits than its factorization.

4200921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27480 (or 27477 counting only the distinct ones).

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

The square root of 4200921 is about 2049.6148418666. The cubic root of 4200921 is about 161.3546571356.

Adding to 4200921 its reverse (1290024), we get a palindrome (5490945).

The spelling of 4200921 in words is "four million, two hundred thousand, nine hundred twenty-one".