820813405 has 8 divisors (see below), whose sum is σ = 1005933312. Its totient is φ = 642679248.

The previous prime is 820813393. The next prime is 820813417. The reversal of 820813405 is 504318028.

It is an interprime number because it is at equal distance from previous prime (820813393) and next prime (820813417).

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 820813405 - 2⁵ = 820813373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 1746177 + ... + 1746646.

It is an arithmetic number, because the mean of its divisors is an integer number (125741664).

Almost surely, 2^820813405 is an apocalyptic number.

It is an amenable number.

820813405 is a deficient number, since it is larger than the sum of its proper divisors (185119907).

820813405 is a wasteful number, since it uses less digits than its factorization.

820813405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3492875.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 820813405 is about 28649.8412735568. The cubic root of 820813405 is about 936.2995474678.

The spelling of 820813405 in words is "eight hundred twenty million, eight hundred thirteen thousand, four hundred five".