666754513 has 2 divisors, whose sum is σ = 666754514. Its totient is φ = 666754512.

The previous prime is 666754511. The next prime is 666754531. The reversal of 666754513 is 315457666.

Together with next prime (666754531) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 485232784 + 181521729 = 22028^2 + 13473^2 .

It is a cyclic number.

It is not a de Polignac number, because 666754513 - 2¹ = 666754511 is a prime.

Together with 666754511, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 666754513.

It is not a weakly prime, because it can be changed into another prime (666754511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333377256 + 333377257.

It is an arithmetic number, because the mean of its divisors is an integer number (333377257).

Almost surely, 2^666754513 is an apocalyptic number.

It is an amenable number.

666754513 is a deficient number, since it is larger than the sum of its proper divisors (1).

666754513 is an equidigital number, since it uses as much as digits as its factorization.

666754513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 43.

The square root of 666754513 is about 25821.5900556104. The cubic root of 666754513 is about 873.6188334714.

The spelling of 666754513 in words is "six hundred sixty-six million, seven hundred fifty-four thousand, five hundred thirteen".