75057921917521 has 2 divisors, whose sum is σ = 75057921917522. Its totient is φ = 75057921917520.

The previous prime is 75057921917519. The next prime is 75057921917549. The reversal of 75057921917521 is 12571912975057.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72278902890000 + 2779019027521 = 8501700^2 + 1667039^2 .

It is a cyclic number.

It is not a de Polignac number, because 75057921917521 - 2¹ = 75057921917519 is a prime.

Together with 75057921917519, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 75057921917521.

It is not a weakly prime, because it can be changed into another prime (75057921917021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37528960958760 + 37528960958761.

It is an arithmetic number, because the mean of its divisors is an integer number (37528960958761).

Almost surely, 2^{75057921917521} is an apocalyptic number.

It is an amenable number.

75057921917521 is a deficient number, since it is larger than the sum of its proper divisors (1).

75057921917521 is an equidigital number, since it uses as much as digits as its factorization.

75057921917521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13891500, while the sum is 61.

The spelling of 75057921917521 in words is "seventy-five trillion, fifty-seven billion, nine hundred twenty-one million, nine hundred seventeen thousand, five hundred twenty-one".