78999997 has 16 divisors (see below), whose sum is σ = 84787200. Its totient is φ = 73476720.

The previous prime is 78999979. The next prime is 79000007. The reversal of 78999997 is 79999987.

It is a cyclic number.

It is not a de Polignac number, because 78999997 - 2¹¹ = 78997949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78999937) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85504 + ... + 86422.

It is an arithmetic number, because the mean of its divisors is an integer number (5299200).

Almost surely, 2^78999997 is an apocalyptic number.

It is an amenable number.

78999997 is a deficient number, since it is larger than the sum of its proper divisors (5787203).

78999997 is a wasteful number, since it uses less digits than its factorization.

78999997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056.

The product of its digits is 23147208, while the sum is 67.

The square root of 78999997 is about 8888.1942485524. The cubic root of 78999997 is about 429.0840372712.

The spelling of 78999997 in words is "seventy-eight million, nine hundred ninety-nine thousand, nine hundred ninety-seven".