820645063 has 8 divisors (see below), whose sum is σ = 993049632. Its totient is φ = 662032896.

The previous prime is 820645009. The next prime is 820645069. The reversal of 820645063 is 360546028.

It is a happy number.

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

It is not a de Polignac number, because 820645063 - 2²⁵ = 787090631 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820645069) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3447970 + ... + 3448207.

It is an arithmetic number, because the mean of its divisors is an integer number (124131204).

Almost surely, 2^820645063 is an apocalyptic number.

820645063 is a deficient number, since it is larger than the sum of its proper divisors (172404569).

820645063 is a wasteful number, since it uses less digits than its factorization.

820645063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6896201.

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 820645063 is about 28646.9032008697. The cubic root of 820645063 is about 936.2355340090.

The spelling of 820645063 in words is "eight hundred twenty million, six hundred forty-five thousand, sixty-three".