666627651 has 20 divisors (see below), whose sum is σ = 1020120024. Its totient is φ = 433576800.

The previous prime is 666627623. The next prime is 666627659. The reversal of 666627651 is 156726666.

It is not a de Polignac number, because 666627651 - 2⁹ = 666627139 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 666627597 and 666627606.

It is not an unprimeable number, because it can be changed into a prime (666627659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 97045 + ... + 103686.

Almost surely, 2^666627651 is an apocalyptic number.

666627651 is a deficient number, since it is larger than the sum of its proper divisors (353492373).

666627651 is a wasteful number, since it uses less digits than its factorization.

666627651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200784 (or 200775 counting only the distinct ones).

The product of its digits is 544320, while the sum is 45.

The square root of 666627651 is about 25819.1334285254. The cubic root of 666627651 is about 873.5634227417.

The spelling of 666627651 in words is "six hundred sixty-six million, six hundred twenty-seven thousand, six hundred fifty-one".