79220857 has 4 divisors (see below), whose sum is σ = 79257700. Its totient is φ = 79184016.

The previous prime is 79220851. The next prime is 79220863. The reversal of 79220857 is 75802297.

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

It is an interprime number because it is at equal distance from previous prime (79220851) and next prime (79220863).

It can be written as a sum of positive squares in 2 ways, for example, as 54110736 + 25110121 = 7356^2 + 5011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79220857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79220851) 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 3 ways as a sum of consecutive naturals, for example, 14982 + ... + 19567.

It is an arithmetic number, because the mean of its divisors is an integer number (19814425).

Almost surely, 2^79220857 is an apocalyptic number.

It is an amenable number.

79220857 is a deficient number, since it is larger than the sum of its proper divisors (36843).

79220857 is a wasteful number, since it uses less digits than its factorization.

79220857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36842.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 79220857 is about 8900.6099229210. The cubic root of 79220857 is about 429.4835281035.

The spelling of 79220857 in words is "seventy-nine million, two hundred twenty thousand, eight hundred fifty-seven".