65726209 has 8 divisors (see below), whose sum is σ = 68097960. Its totient is φ = 63361536.

The previous prime is 65726189. The next prime is 65726251. The reversal of 65726209 is 90262756.

It can be written as a sum of positive squares in 4 ways, for example, as 2873025 + 62853184 = 1695^2 + 7928^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 65726209 - 2⁷ = 65726081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65726279) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23409 + ... + 26065.

It is an arithmetic number, because the mean of its divisors is an integer number (8512245).

Almost surely, 2^65726209 is an apocalyptic number.

It is an amenable number.

65726209 is a deficient number, since it is larger than the sum of its proper divisors (2371751).

65726209 is a wasteful number, since it uses less digits than its factorization.

65726209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3539.

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 65726209 is about 8107.1702214768. The cubic root of 65726209 is about 403.5644118251.

The spelling of 65726209 in words is "sixty-five million, seven hundred twenty-six thousand, two hundred nine".