74545781 has 2 divisors, whose sum is σ = 74545782. Its totient is φ = 74545780.

The previous prime is 74545753. The next prime is 74545817. The reversal of 74545781 is 18754547.

Together with next prime (74545817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41667025 + 32878756 = 6455^2 + 5734^2 .

It is a cyclic number.

It is not a de Polignac number, because 74545781 - 2⁶ = 74545717 is a prime.

It is a super-2 number, since 2×74545781² = 11114146929799922, which contains 22 as substring.

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 (74545711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37272890 + 37272891.

It is an arithmetic number, because the mean of its divisors is an integer number (37272891).

Almost surely, 2^74545781 is an apocalyptic number.

It is an amenable number.

74545781 is a deficient number, since it is larger than the sum of its proper divisors (1).

74545781 is an equidigital number, since it uses as much as digits as its factorization.

74545781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 156800, while the sum is 41.

The square root of 74545781 is about 8633.9898656415. The cubic root of 74545781 is about 420.8632678856.

The spelling of 74545781 in words is "seventy-four million, five hundred forty-five thousand, seven hundred eighty-one".