76666691 has 16 divisors (see below), whose sum is σ = 84890400. Its totient is φ = 68947200.

The previous prime is 76666663. The next prime is 76666703. The reversal of 76666691 is 19666667.

It is not a de Polignac number, because 76666691 - 2¹⁴ = 76650307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (76666621) 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 15 ways as a sum of consecutive naturals, for example, 32471 + ... + 34751.

It is an arithmetic number, because the mean of its divisors is an integer number (5305650).

Almost surely, 2^76666691 is an apocalyptic number.

76666691 is a deficient number, since it is larger than the sum of its proper divisors (8223709).

76666691 is a wasteful number, since it uses less digits than its factorization.

76666691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2390.

The product of its digits is 489888, while the sum is 47.

The square root of 76666691 is about 8755.9517472403. The cubic root of 76666691 is about 424.8173443472.

The spelling of 76666691 in words is "seventy-six million, six hundred sixty-six thousand, six hundred ninety-one".