66356849 has 4 divisors (see below), whose sum is σ = 71461236. Its totient is φ = 61252464.

The previous prime is 66356839. The next prime is 66356879. The reversal of 66356849 is 94865366.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11122225 + 55234624 = 3335^2 + 7432^2 .

It is a de Polignac number, because none of the positive numbers 2^k-66356849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66356839) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2552174 + ... + 2552199.

It is an arithmetic number, because the mean of its divisors is an integer number (17865309).

Almost surely, 2^66356849 is an apocalyptic number.

It is an amenable number.

66356849 is a deficient number, since it is larger than the sum of its proper divisors (5104387).

66356849 is a wasteful number, since it uses less digits than its factorization.

66356849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5104386.

The product of its digits is 933120, while the sum is 47.

The square root of 66356849 is about 8145.9713355744. The cubic root of 66356849 is about 404.8510329544.

The spelling of 66356849 in words is "sixty-six million, three hundred fifty-six thousand, eight hundred forty-nine".