490871021 has 2 divisors, whose sum is σ = 490871022. Its totient is φ = 490871020.

The previous prime is 490870997. The next prime is 490871027. The reversal of 490871021 is 120178094.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 340808521 + 150062500 = 18461^2 + 12250^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-490871021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (490871027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245435510 + 245435511.

It is an arithmetic number, because the mean of its divisors is an integer number (245435511).

Almost surely, 2^490871021 is an apocalyptic number.

It is an amenable number.

490871021 is a deficient number, since it is larger than the sum of its proper divisors (1).

490871021 is an equidigital number, since it uses as much as digits as its factorization.

490871021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 490871021 is about 22155.6092446134. The cubic root of 490871021 is about 788.8403757695.

The spelling of 490871021 in words is "four hundred ninety million, eight hundred seventy-one thousand, twenty-one".