7210878121 has 2 divisors, whose sum is σ = 7210878122. Its totient is φ = 7210878120.

The previous prime is 7210878109. The next prime is 7210878131. The reversal of 7210878121 is 1218780127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5706291600 + 1504586521 = 75540^2 + 38789^2 .

It is an emirp because it is prime and its reverse (1218780127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7210878121 - 2¹⁵ = 7210845353 is a prime.

It is not a weakly prime, because it can be changed into another prime (7210878131) 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 as a sum of consecutive naturals, namely, 3605439060 + 3605439061.

It is an arithmetic number, because the mean of its divisors is an integer number (3605439061).

Almost surely, 2^7210878121 is an apocalyptic number.

It is an amenable number.

7210878121 is a deficient number, since it is larger than the sum of its proper divisors (1).

7210878121 is an equidigital number, since it uses as much as digits as its factorization.

7210878121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12544, while the sum is 37.

The square root of 7210878121 is about 84916.8894920204. The cubic root of 7210878121 is about 1931.9507530487.

The spelling of 7210878121 in words is "seven billion, two hundred ten million, eight hundred seventy-eight thousand, one hundred twenty-one".