74666681 has 2 divisors, whose sum is σ = 74666682. Its totient is φ = 74666680.

The previous prime is 74666659. The next prime is 74666701. The reversal of 74666681 is 18666647.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73188025 + 1478656 = 8555^2 + 1216^2 .

It is an emirp because it is prime and its reverse (18666647) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-74666681 is a prime.

It is a super-2 number, since 2×74666681² = 11150226503111522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (74666611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37333340 + 37333341.

It is an arithmetic number, because the mean of its divisors is an integer number (37333341).

Almost surely, 2^74666681 is an apocalyptic number.

It is an amenable number.

74666681 is a deficient number, since it is larger than the sum of its proper divisors (1).

74666681 is an equidigital number, since it uses as much as digits as its factorization.

74666681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 44.

The square root of 74666681 is about 8640.9884272576. The cubic root of 74666681 is about 421.0906667885.

The spelling of 74666681 in words is "seventy-four million, six hundred sixty-six thousand, six hundred eighty-one".