76666661 has 4 divisors (see below), whose sum is σ = 76746912. Its totient is φ = 76586412.

The previous prime is 76666657. The next prime is 76666663. The reversal of 76666661 is 16666667.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 76666661 - 2² = 76666657 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (76666663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38675 + ... + 40608.

It is an arithmetic number, because the mean of its divisors is an integer number (19186728).

Almost surely, 2^76666661 is an apocalyptic number.

It is an amenable number.

76666661 is a deficient number, since it is larger than the sum of its proper divisors (80251).

76666661 is an equidigital number, since it uses as much as digits as its factorization.

76666661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80250.

The product of its digits is 326592, while the sum is 44.

The square root of 76666661 is about 8755.9500341197. The cubic root of 76666661 is about 424.8172889363.

It can be divided in two parts, 7666666 and 1, that added together give a palindrome (7666667).

The spelling of 76666661 in words is "seventy-six million, six hundred sixty-six thousand, six hundred sixty-one".