65720771 has 4 divisors (see below), whose sum is σ = 66162000. Its totient is φ = 65279544.

The previous prime is 65720747. The next prime is 65720773. The reversal of 65720771 is 17702756.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65720771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65720773) 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, 220391 + ... + 220688.

It is an arithmetic number, because the mean of its divisors is an integer number (16540500).

Almost surely, 2^65720771 is an apocalyptic number.

65720771 is a deficient number, since it is larger than the sum of its proper divisors (441229).

65720771 is a wasteful number, since it uses less digits than its factorization.

65720771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441228.

The product of its (nonzero) digits is 20580, while the sum is 35.

The square root of 65720771 is about 8106.8348324115. The cubic root of 65720771 is about 403.5532815934.

The spelling of 65720771 in words is "sixty-five million, seven hundred twenty thousand, seven hundred seventy-one".