666734287 has 2 divisors, whose sum is σ = 666734288. Its totient is φ = 666734286.

The previous prime is 666734261. The next prime is 666734363. The reversal of 666734287 is 782437666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666734287 - 2¹¹ = 666732239 is a prime.

It is a super-2 number, since 2×666734287² = 889069218922796738, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 666734287.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666734207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333367143 + 333367144.

It is an arithmetic number, because the mean of its divisors is an integer number (333367144).

Almost surely, 2^666734287 is an apocalyptic number.

666734287 is a deficient number, since it is larger than the sum of its proper divisors (1).

666734287 is an equidigital number, since it uses as much as digits as its factorization.

666734287 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2032128, while the sum is 49.

The square root of 666734287 is about 25821.1984036373. The cubic root of 666734287 is about 873.6099996389.

The spelling of 666734287 in words is "six hundred sixty-six million, seven hundred thirty-four thousand, two hundred eighty-seven".