666551007 has 12 divisors (see below), whose sum is σ = 972144784. Its totient is φ = 440052480.

The previous prime is 666550999. The next prime is 666551029. The reversal of 666551007 is 700155666.

It is a happy number.

It is not a de Polignac number, because 666551007 - 2³ = 666550999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666551077) 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 11 ways as a sum of consecutive naturals, for example, 358594 + ... + 360447.

Almost surely, 2^666551007 is an apocalyptic number.

666551007 is a deficient number, since it is larger than the sum of its proper divisors (305593777).

666551007 is a wasteful number, since it uses less digits than its factorization.

666551007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719150 (or 719147 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 666551007 is about 25817.6491377507. The cubic root of 666551007 is about 873.5299428018.

The spelling of 666551007 in words is "six hundred sixty-six million, five hundred fifty-one thousand, seven".