820686845 has 8 divisors (see below), whose sum is σ = 1074353760. Its totient is φ = 596863120.

The previous prime is 820686767. The next prime is 820686857. The reversal of 820686845 is 548686028.

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

It is not a de Polignac number, because 820686845 - 2¹² = 820682749 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 820686845.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7460735 + ... + 7460844.

It is an arithmetic number, because the mean of its divisors is an integer number (134294220).

Almost surely, 2^820686845 is an apocalyptic number.

It is an amenable number.

820686845 is a deficient number, since it is larger than the sum of its proper divisors (253666915).

820686845 is a wasteful number, since it uses less digits than its factorization.

820686845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14921595.

The product of its (nonzero) digits is 737280, while the sum is 47.

The square root of 820686845 is about 28647.6324501694. The cubic root of 820686845 is about 936.2514227820.

The spelling of 820686845 in words is "eight hundred twenty million, six hundred eighty-six thousand, eight hundred forty-five".