66158641 has 2 divisors, whose sum is σ = 66158642. Its totient is φ = 66158640.

The previous prime is 66158623. The next prime is 66158671. The reversal of 66158641 is 14685166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48011041 + 18147600 = 6929^2 + 4260^2 .

It is a cyclic number.

It is not a de Polignac number, because 66158641 - 2¹³ = 66150449 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66158641.

It is not a weakly prime, because it can be changed into another prime (66158621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33079320 + 33079321.

It is an arithmetic number, because the mean of its divisors is an integer number (33079321).

Almost surely, 2^66158641 is an apocalyptic number.

It is an amenable number.

66158641 is a deficient number, since it is larger than the sum of its proper divisors (1).

66158641 is an equidigital number, since it uses as much as digits as its factorization.

66158641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 37.

The square root of 66158641 is about 8133.7962231666. The cubic root of 66158641 is about 404.4475340711.

The spelling of 66158641 in words is "sixty-six million, one hundred fifty-eight thousand, six hundred forty-one".