78821039806 has 16 divisors (see below), whose sum is σ = 120045873024. Its totient is φ = 38808842904.

The previous prime is 78821039789. The next prime is 78821039807. The reversal of 78821039806 is 60893012887.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78821039807) 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, 722370 + ... + 824293.

It is an arithmetic number, because the mean of its divisors is an integer number (7502867064).

Almost surely, 2^78821039806 is an apocalyptic number.

78821039806 is a deficient number, since it is larger than the sum of its proper divisors (41224833218).

78821039806 is a wasteful number, since it uses less digits than its factorization.

78821039806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1547055.

The product of its (nonzero) digits is 1161216, while the sum is 52.

The spelling of 78821039806 in words is "seventy-eight billion, eight hundred twenty-one million, thirty-nine thousand, eight hundred six".