490921 has 2 divisors, whose sum is σ = 490922. Its totient is φ = 490920.

The previous prime is 490913. The next prime is 490927. The reversal of 490921 is 129094.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 275625 + 215296 = 525^2 + 464^2 .

It is a cyclic number.

It is not a de Polignac number, because 490921 - 2³ = 490913 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (490927) 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 as a sum of consecutive naturals, namely, 245460 + 245461.

It is an arithmetic number, because the mean of its divisors is an integer number (245461).

2⁴⁹⁰⁹²¹ is an apocalyptic number.

It is an amenable number.

490921 is a deficient number, since it is larger than the sum of its proper divisors (1).

490921 is an equidigital number, since it uses as much as digits as its factorization.

490921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 490921 is about 700.6575483073. The cubic root of 490921 is about 78.8867147307.

The spelling of 490921 in words is "four hundred ninety thousand, nine hundred twenty-one".