79977805 has 4 divisors (see below), whose sum is σ = 95973372. Its totient is φ = 63982240.

The previous prime is 79977773. The next prime is 79977817. The reversal of 79977805 is 50877997.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35928036 + 44049769 = 5994^2 + 6637^2 .

It is not a de Polignac number, because 79977805 - 2⁵ = 79977773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 7997776 + ... + 7997785.

It is an arithmetic number, because the mean of its divisors is an integer number (23993343).

Almost surely, 2^79977805 is an apocalyptic number.

It is an amenable number.

79977805 is a deficient number, since it is larger than the sum of its proper divisors (15995567).

79977805 is a wasteful number, since it uses less digits than its factorization.

79977805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15995566.

The product of its (nonzero) digits is 1111320, while the sum is 52.

The square root of 79977805 is about 8943.0310857114. The cubic root of 79977805 is about 430.8470862557.

The spelling of 79977805 in words is "seventy-nine million, nine hundred seventy-seven thousand, eight hundred five".