79800121 has 2 divisors, whose sum is σ = 79800122. Its totient is φ = 79800120.

The previous prime is 79800109. The next prime is 79800143. The reversal of 79800121 is 12100897.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41422096 + 38378025 = 6436^2 + 6195^2 .

It is a cyclic number.

It is not a de Polignac number, because 79800121 - 2¹⁵ = 79767353 is a prime.

It is a super-2 number, since 2×79800121² = 12736118623229282, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 79800121.

It is not a weakly prime, because it can be changed into another prime (79800151) 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 as a sum of consecutive naturals, namely, 39900060 + 39900061.

It is an arithmetic number, because the mean of its divisors is an integer number (39900061).

Almost surely, 2^79800121 is an apocalyptic number.

It is an amenable number.

79800121 is a deficient number, since it is larger than the sum of its proper divisors (1).

79800121 is an equidigital number, since it uses as much as digits as its factorization.

79800121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 79800121 is about 8933.0913462250. The cubic root of 79800121 is about 430.5277835163.

The spelling of 79800121 in words is "seventy-nine million, eight hundred thousand, one hundred twenty-one".