7491777666 has 16 divisors (see below), whose sum is σ = 15017383584. Its totient is φ = 2491621184.

The previous prime is 7491777619. The next prime is 7491777677. The reversal of 7491777666 is 6667771947.

It is a super-3 number, since 3×7491777666³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1406631 + ... + 1411946.

It is an arithmetic number, because the mean of its divisors is an integer number (938586474).

Almost surely, 2^7491777666 is an apocalyptic number.

7491777666 is an abundant number, since it is smaller than the sum of its proper divisors (7525605918).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7491777666 is a wasteful number, since it uses less digits than its factorization.

7491777666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2819025.

The product of its digits is 18670176, while the sum is 60.

The square root of 7491777666 is about 86555.0556928941. The cubic root of 7491777666 is about 1956.7182401475.

The spelling of 7491777666 in words is "seven billion, four hundred ninety-one million, seven hundred seventy-seven thousand, six hundred sixty-six".