78753121 has 2 divisors, whose sum is σ = 78753122. Its totient is φ = 78753120.

The previous prime is 78753053. The next prime is 78753137. The reversal of 78753121 is 12135787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71656225 + 7096896 = 8465^2 + 2664^2 .

It is a cyclic number.

It is not a de Polignac number, because 78753121 - 2¹¹ = 78751073 is a prime.

It is not a weakly prime, because it can be changed into another prime (78753421) 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, 39376560 + 39376561.

It is an arithmetic number, because the mean of its divisors is an integer number (39376561).

Almost surely, 2^78753121 is an apocalyptic number.

It is an amenable number.

78753121 is a deficient number, since it is larger than the sum of its proper divisors (1).

78753121 is an equidigital number, since it uses as much as digits as its factorization.

78753121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11760, while the sum is 34.

The square root of 78753121 is about 8874.2955213358. The cubic root of 78753121 is about 428.6366065051.

The spelling of 78753121 in words is "seventy-eight million, seven hundred fifty-three thousand, one hundred twenty-one".