65206661 has 4 divisors (see below), whose sum is σ = 70222572. Its totient is φ = 60190752.

The previous prime is 65206637. The next prime is 65206663. The reversal of 65206661 is 16660256.

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 3976036 + 61230625 = 1994^2 + 7825^2 .

It is a cyclic number.

It is not a de Polignac number, because 65206661 - 2¹⁴ = 65190277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65206663) 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, 2507936 + ... + 2507961.

It is an arithmetic number, because the mean of its divisors is an integer number (17555643).

Almost surely, 2^65206661 is an apocalyptic number.

It is an amenable number.

65206661 is a deficient number, since it is larger than the sum of its proper divisors (5015911).

65206661 is a wasteful number, since it uses less digits than its factorization.

65206661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5015910.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 65206661 is about 8075.0641483520. The cubic root of 65206661 is about 402.4982415725.

The spelling of 65206661 in words is "sixty-five million, two hundred six thousand, six hundred sixty-one".