75121261 has 2 divisors, whose sum is σ = 75121262. Its totient is φ = 75121260.

The previous prime is 75121259. The next prime is 75121273. The reversal of 75121261 is 16212157.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46498761 + 28622500 = 6819^2 + 5350^2 .

It is a cyclic number.

It is not a de Polignac number, because 75121261 - 2¹ = 75121259 is a prime.

Together with 75121259, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75121201) 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, 37560630 + 37560631.

It is an arithmetic number, because the mean of its divisors is an integer number (37560631).

Almost surely, 2^75121261 is an apocalyptic number.

It is an amenable number.

75121261 is a deficient number, since it is larger than the sum of its proper divisors (1).

75121261 is an equidigital number, since it uses as much as digits as its factorization.

75121261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 840, while the sum is 25.

The square root of 75121261 is about 8667.2522173985. The cubic root of 75121261 is about 421.9434891348.

The spelling of 75121261 in words is "seventy-five million, one hundred twenty-one thousand, two hundred sixty-one".