8502421 has 4 divisors (see below), whose sum is σ = 8509644. Its totient is φ = 8495200.

The previous prime is 8502409. The next prime is 8502449. The reversal of 8502421 is 1242058.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1242058 = 2 ⋅621029.

It can be written as a sum of positive squares in 2 ways, for example, as 3944196 + 4558225 = 1986^2 + 2135^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8502421 is a prime.

It is a super-2 number, since 2×8502421² = 144582325722482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8502392 and 8502401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8502121) 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 3 ways as a sum of consecutive naturals, for example, 1390 + ... + 4351.

It is an arithmetic number, because the mean of its divisors is an integer number (2127411).

Almost surely, 2^8502421 is an apocalyptic number.

It is an amenable number.

8502421 is a deficient number, since it is larger than the sum of its proper divisors (7223).

8502421 is a wasteful number, since it uses less digits than its factorization.

8502421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7222.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 8502421 is about 2915.8911159369. The cubic root of 8502421 is about 204.1021291135.

Adding to 8502421 its reverse (1242058), we get a palindrome (9744479).

The spelling of 8502421 in words is "eight million, five hundred two thousand, four hundred twenty-one".