820667671685 has 8 divisors (see below), whose sum is σ = 984806324736. Its totient is φ = 656530724880.

The previous prime is 820667671679. The next prime is 820667671687. The reversal of 820667671685 is 586176766028.

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

It is a de Polignac number, because none of the positive numbers 2^k-820667671685 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820667671687) 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, 1185332 + ... + 1745378.

It is an arithmetic number, because the mean of its divisors is an integer number (123100790592).

Almost surely, 2^820667671685 is an apocalyptic number.

It is an amenable number.

820667671685 is a deficient number, since it is larger than the sum of its proper divisors (164138653051).

820667671685 is a wasteful number, since it uses less digits than its factorization.

820667671685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 853123.

The product of its (nonzero) digits is 40642560, while the sum is 62.

The spelling of 820667671685 in words is "eight hundred twenty billion, six hundred sixty-seven million, six hundred seventy-one thousand, six hundred eighty-five".