74756843609621 has 2 divisors, whose sum is σ = 74756843609622. Its totient is φ = 74756843609620.

The previous prime is 74756843609603. The next prime is 74756843609663. The reversal of 74756843609621 is 12690634865747.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68197636010596 + 6559207599025 = 8258186^2 + 2561095^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-74756843609621 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (74756843605621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37378421804810 + 37378421804811.

It is an arithmetic number, because the mean of its divisors is an integer number (37378421804811).

It is a 1-persistent number, because it is pandigital, but 2⋅74756843609621 = 149513687219242 is not.

Almost surely, 2^{74756843609621} is an apocalyptic number.

It is an amenable number.

74756843609621 is a deficient number, since it is larger than the sum of its proper divisors (1).

74756843609621 is an equidigital number, since it uses as much as digits as its factorization.

74756843609621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 365783040, while the sum is 68.

The spelling of 74756843609621 in words is "seventy-four trillion, seven hundred fifty-six billion, eight hundred forty-three million, six hundred nine thousand, six hundred twenty-one".