820378861445 has 64 divisors (see below), whose sum is σ = 1236486311424. Its totient is φ = 513313873920.

The previous prime is 820378861399. The next prime is 820378861459. The reversal of 820378861445 is 544168873028.

It is not a de Polignac number, because 820378861445 - 2²⁰ = 820377812869 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 924329 + ... + 1579601.

It is an arithmetic number, because the mean of its divisors is an integer number (19320098616).

Almost surely, 2^820378861445 is an apocalyptic number.

820378861445 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

820378861445 is a deficient number, since it is larger than the sum of its proper divisors (416107449979).

820378861445 is a wasteful number, since it uses less digits than its factorization.

820378861445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 655422.

The product of its (nonzero) digits is 10321920, while the sum is 56.

The spelling of 820378861445 in words is "eight hundred twenty billion, three hundred seventy-eight million, eight hundred sixty-one thousand, four hundred forty-five".