75656601256921 has 2 divisors, whose sum is σ = 75656601256922. Its totient is φ = 75656601256920.

The previous prime is 75656601256883. The next prime is 75656601256949. The reversal of 75656601256921 is 12965210665657.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45057172951296 + 30599428305625 = 6712464^2 + 5531675^2 .

It is a cyclic number.

It is not a de Polignac number, because 75656601256921 - 2¹¹ = 75656601254873 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 75656601256921.

It is not a weakly prime, because it can be changed into another prime (75656601256021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37828300628460 + 37828300628461.

It is an arithmetic number, because the mean of its divisors is an integer number (37828300628461).

Almost surely, 2^{75656601256921} is an apocalyptic number.

It is an amenable number.

75656601256921 is a deficient number, since it is larger than the sum of its proper divisors (1).

75656601256921 is an equidigital number, since it uses as much as digits as its factorization.

75656601256921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824000, while the sum is 61.

The spelling of 75656601256921 in words is "seventy-five trillion, six hundred fifty-six billion, six hundred one million, two hundred fifty-six thousand, nine hundred twenty-one".