8428121 has 4 divisors (see below), whose sum is σ = 9076452. Its totient is φ = 7779792.

The previous prime is 8428099. The next prime is 8428139. The reversal of 8428121 is 1218248.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2371600 + 6056521 = 1540^2 + 2461^2 .

It is a cyclic number.

It is not a de Polignac number, because 8428121 - 2¹⁸ = 8165977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8428171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324146 + ... + 324171.

It is an arithmetic number, because the mean of its divisors is an integer number (2269113).

Almost surely, 2^8428121 is an apocalyptic number.

It is an amenable number.

8428121 is a deficient number, since it is larger than the sum of its proper divisors (648331).

8428121 is a wasteful number, since it uses less digits than its factorization.

8428121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648330.

The product of its digits is 1024, while the sum is 26.

The square root of 8428121 is about 2903.1226291702. The cubic root of 8428121 is about 203.5058606172.

The spelling of 8428121 in words is "eight million, four hundred twenty-eight thousand, one hundred twenty-one".