9812421 has 30 divisors (see below), whose sum is σ = 15389990. Its totient is φ = 6229872.

The previous prime is 9812393. The next prime is 9812431. The reversal of 9812421 is 1242189.

It can be written as a sum of positive squares in only one way, i.e., 9641025 + 171396 = 3105^2 + 414^2 .

It is not a de Polignac number, because 9812421 - 2⁵ = 9812389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

9812421 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9812431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 42735 + ... + 42963.

Almost surely, 2^9812421 is an apocalyptic number.

It is an amenable number.

9812421 is a deficient number, since it is larger than the sum of its proper divisors (5577569).

9812421 is a wasteful number, since it uses less digits than its factorization.

9812421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287 (or 255 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 9812421 is about 3132.4784117373. The cubic root of 9812421 is about 214.0878682458.

The spelling of 9812421 in words is "nine million, eight hundred twelve thousand, four hundred twenty-one".