65979889 has 4 divisors (see below), whose sum is σ = 66039460. Its totient is φ = 65920320.

The previous prime is 65979887. The next prime is 65979899. The reversal of 65979889 is 98897956.

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 34810000 + 31169889 = 5900^2 + 5583^2 .

It is a cyclic number.

It is not a de Polignac number, because 65979889 - 2¹ = 65979887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65979887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28092 + ... + 30349.

It is an arithmetic number, because the mean of its divisors is an integer number (16509865).

Almost surely, 2^65979889 is an apocalyptic number.

It is an amenable number.

65979889 is a deficient number, since it is larger than the sum of its proper divisors (59571).

65979889 is a wasteful number, since it uses less digits than its factorization.

65979889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59570.

The product of its digits is 9797760, while the sum is 61.

The square root of 65979889 is about 8122.8005638450. The cubic root of 65979889 is about 404.0829507317.

The spelling of 65979889 in words is "sixty-five million, nine hundred seventy-nine thousand, eight hundred eighty-nine".