78821942 has 16 divisors (see below), whose sum is σ = 122839200. Its totient is φ = 37887360.

The previous prime is 78821927. The next prime is 78821947. The reversal of 78821942 is 24912887.

It is a self number, because there is not a number n which added to its sum of digits gives 78821942.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78821947) 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, 11159 + ... + 16797.

It is an arithmetic number, because the mean of its divisors is an integer number (7677450).

Almost surely, 2^78821942 is an apocalyptic number.

78821942 is a deficient number, since it is larger than the sum of its proper divisors (44017258).

78821942 is a wasteful number, since it uses less digits than its factorization.

78821942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5911.

The product of its digits is 64512, while the sum is 41.

The square root of 78821942 is about 8878.1722218033. The cubic root of 78821942 is about 428.7614295417.

The spelling of 78821942 in words is "seventy-eight million, eight hundred twenty-one thousand, nine hundred forty-two".