78819897 has 16 divisors (see below), whose sum is σ = 113762880. Its totient is φ = 48253632.

The previous prime is 78819877. The next prime is 78819901. The reversal of 78819897 is 79891887.

It is not a de Polignac number, because 78819897 - 2⁶ = 78819833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78819857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2554 + ... + 12812.

It is an arithmetic number, because the mean of its divisors is an integer number (7110180).

Almost surely, 2^78819897 is an apocalyptic number.

It is an amenable number.

78819897 is a deficient number, since it is larger than the sum of its proper divisors (34942983).

78819897 is a wasteful number, since it uses less digits than its factorization.

78819897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10472.

The product of its digits is 2032128, while the sum is 57.

The square root of 78819897 is about 8878.0570509543. The cubic root of 78819897 is about 428.7577215019.

The spelling of 78819897 in words is "seventy-eight million, eight hundred nineteen thousand, eight hundred ninety-seven".