72868121 has 2 divisors, whose sum is σ = 72868122. Its totient is φ = 72868120.

The previous prime is 72868093. The next prime is 72868123. The reversal of 72868121 is 12186827.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50410000 + 22458121 = 7100^2 + 4739^2 .

It is an emirp because it is prime and its reverse (12186827) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72868121 is a prime.

Together with 72868123, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72868123) 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, 36434060 + 36434061.

It is an arithmetic number, because the mean of its divisors is an integer number (36434061).

Almost surely, 2^72868121 is an apocalyptic number.

It is an amenable number.

72868121 is a deficient number, since it is larger than the sum of its proper divisors (1).

72868121 is an equidigital number, since it uses as much as digits as its factorization.

72868121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10752, while the sum is 35.

The square root of 72868121 is about 8536.2826218442. The cubic root of 72868121 is about 417.6820934677.

The spelling of 72868121 in words is "seventy-two million, eight hundred sixty-eight thousand, one hundred twenty-one".