666042551 has 8 divisors (see below), whose sum is σ = 676084608. Its totient is φ = 656019000.

The previous prime is 666042479. The next prime is 666042569. The reversal of 666042551 is 155240666.

666042551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 666042551 - 2²² = 661848247 is a prime.

It is a super-3 number, since 3×666042551³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666012551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79136 + ... + 87146.

It is an arithmetic number, because the mean of its divisors is an integer number (84510576).

Almost surely, 2^666042551 is an apocalyptic number.

666042551 is a deficient number, since it is larger than the sum of its proper divisors (10042057).

666042551 is a wasteful number, since it uses less digits than its factorization.

666042551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9253.

The product of its (nonzero) digits is 43200, while the sum is 35.

The square root of 666042551 is about 25807.8001968397. The cubic root of 666042551 is about 873.3077719956.

The spelling of 666042551 in words is "six hundred sixty-six million, forty-two thousand, five hundred fifty-one".