10421921 has 16 divisors (see below), whose sum is σ = 11501568. Its totient is φ = 9411600.

The previous prime is 10421909. The next prime is 10421947. The reversal of 10421921 is 12912401.

It is not a de Polignac number, because 10421921 - 2¹⁴ = 10405537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 10421893 and 10421902.

It is not an unprimeable number, because it can be changed into a prime (10421951) 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 15 ways as a sum of consecutive naturals, for example, 33356 + ... + 33666.

It is an arithmetic number, because the mean of its divisors is an integer number (718848).

Almost surely, 2^10421921 is an apocalyptic number.

It is an amenable number.

10421921 is a deficient number, since it is larger than the sum of its proper divisors (1079647).

10421921 is a wasteful number, since it uses less digits than its factorization.

10421921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 10421921 is about 3228.3000170368. The cubic root of 10421921 is about 218.4318306753.

The spelling of 10421921 in words is "ten million, four hundred twenty-one thousand, nine hundred twenty-one".