74757186521 has 2 divisors, whose sum is σ = 74757186522. Its totient is φ = 74757186520.

The previous prime is 74757186487. The next prime is 74757186523. The reversal of 74757186521 is 12568175747.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74207752921 + 549433600 = 272411^2 + 23440^2 .

It is an emirp because it is prime and its reverse (12568175747) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 74757186521 - 2⁶ = 74757186457 is a prime.

Together with 74757186523, 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 (74757186523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37378593260 + 37378593261.

It is an arithmetic number, because the mean of its divisors is an integer number (37378593261).

Almost surely, 2^74757186521 is an apocalyptic number.

It is an amenable number.

74757186521 is a deficient number, since it is larger than the sum of its proper divisors (1).

74757186521 is an equidigital number, since it uses as much as digits as its factorization.

74757186521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3292800, while the sum is 53.

The spelling of 74757186521 in words is "seventy-four billion, seven hundred fifty-seven million, one hundred eighty-six thousand, five hundred twenty-one".