79100221 has 4 divisors (see below), whose sum is σ = 80592732. Its totient is φ = 77607712.

The previous prime is 79100213. The next prime is 79100227. The reversal of 79100221 is 12200197.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12200197 = 59 ⋅206783.

It can be written as a sum of positive squares in 2 ways, for example, as 59074596 + 20025625 = 7686^2 + 4475^2 .

It is a cyclic number.

It is not a de Polignac number, because 79100221 - 2³ = 79100213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 79100192 and 79100201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79100227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 746176 + ... + 746281.

It is an arithmetic number, because the mean of its divisors is an integer number (20148183).

Almost surely, 2^79100221 is an apocalyptic number.

It is an amenable number.

79100221 is a deficient number, since it is larger than the sum of its proper divisors (1492511).

79100221 is a wasteful number, since it uses less digits than its factorization.

79100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1492510.

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 79100221 is about 8893.8305020953. The cubic root of 79100221 is about 429.2654142626.

The spelling of 79100221 in words is "seventy-nine million, one hundred thousand, two hundred twenty-one".