9872421 has 16 divisors (see below), whose sum is σ = 14271936. Its totient is φ = 6034176.

The previous prime is 9872417. The next prime is 9872437. The reversal of 9872421 is 1242789.

It is a happy number.

It is not a de Polignac number, because 9872421 - 2² = 9872417 is a prime.

9872421 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9872321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5581 + ... + 7133.

It is an arithmetic number, because the mean of its divisors is an integer number (891996).

Almost surely, 2^9872421 is an apocalyptic number.

It is an amenable number.

9872421 is a deficient number, since it is larger than the sum of its proper divisors (4399515).

9872421 is a wasteful number, since it uses less digits than its factorization.

9872421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1732.

The product of its digits is 8064, while the sum is 33.

The square root of 9872421 is about 3142.0408972513. The cubic root of 9872421 is about 214.5233428012.

The spelling of 9872421 in words is "nine million, eight hundred seventy-two thousand, four hundred twenty-one".