820495247 has 8 divisors (see below), whose sum is σ = 963938640. Its totient is φ = 688527360.

The previous prime is 820495217. The next prime is 820495271. The reversal of 820495247 is 742594028.

820495247 = 2324² + 2325² + ... + 2466².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 820495247 - 2¹² = 820491151 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820495217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2868722 + ... + 2869007.

It is an arithmetic number, because the mean of its divisors is an integer number (120492330).

Almost surely, 2^820495247 is an apocalyptic number.

820495247 is a deficient number, since it is larger than the sum of its proper divisors (143443393).

820495247 is a wasteful number, since it uses less digits than its factorization.

820495247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5737753.

The product of its (nonzero) digits is 161280, while the sum is 41.

The square root of 820495247 is about 28644.2882089955. The cubic root of 820495247 is about 936.1785578548.

The spelling of 820495247 in words is "eight hundred twenty million, four hundred ninety-five thousand, two hundred forty-seven".