9766666421 has 8 divisors (see below), whose sum is σ = 9940397760. Its totient is φ = 9593208352.

The previous prime is 9766666417. The next prime is 9766666471. The reversal of 9766666421 is 1246666679.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9766666421 - 2² = 9766666417 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 (9766666471) 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 7 ways as a sum of consecutive naturals, for example, 4481 + ... + 139833.

It is an arithmetic number, because the mean of its divisors is an integer number (1242549720).

Almost surely, 2^9766666421 is an apocalyptic number.

It is an amenable number.

9766666421 is a deficient number, since it is larger than the sum of its proper divisors (173731339).

9766666421 is a wasteful number, since it uses less digits than its factorization.

9766666421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136635.

The product of its digits is 3919104, while the sum is 53.

The square root of 9766666421 is about 98826.4459595710. The cubic root of 9766666421 is about 2137.5459116525.

The spelling of 9766666421 in words is "nine billion, seven hundred sixty-six million, six hundred sixty-six thousand, four hundred twenty-one".