8490421 has 2 divisors, whose sum is σ = 8490422. Its totient is φ = 8490420.

The previous prime is 8490413. The next prime is 8490439. The reversal of 8490421 is 1240948.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7980625 + 509796 = 2825^2 + 714^2 .

It is a cyclic number.

It is not a de Polignac number, because 8490421 - 2³ = 8490413 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8490421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8490401) 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 as a sum of consecutive naturals, namely, 4245210 + 4245211.

It is an arithmetic number, because the mean of its divisors is an integer number (4245211).

Almost surely, 2^8490421 is an apocalyptic number.

It is an amenable number.

8490421 is a deficient number, since it is larger than the sum of its proper divisors (1).

8490421 is an equidigital number, since it uses as much as digits as its factorization.

8490421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 8490421 is about 2913.8326993841. The cubic root of 8490421 is about 204.0060631929.

It can be divided in two parts, 8490 and 421, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 8490421 in words is "eight million, four hundred ninety thousand, four hundred twenty-one".