820490887 has 2 divisors, whose sum is σ = 820490888. Its totient is φ = 820490886.

The previous prime is 820490861. The next prime is 820490899. The reversal of 820490887 is 788094028.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820490887 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820490807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410245443 + 410245444.

It is an arithmetic number, because the mean of its divisors is an integer number (410245444).

Almost surely, 2^820490887 is an apocalyptic number.

820490887 is a deficient number, since it is larger than the sum of its proper divisors (1).

820490887 is an equidigital number, since it uses as much as digits as its factorization.

820490887 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 258048, while the sum is 46.

The square root of 820490887 is about 28644.2121029712. The cubic root of 820490887 is about 936.1768996101.

The spelling of 820490887 in words is "eight hundred twenty million, four hundred ninety thousand, eight hundred eighty-seven".