65721163 has 4 divisors (see below), whose sum is σ = 67987440. Its totient is φ = 63454888.

The previous prime is 65721121. The next prime is 65721169. The reversal of 65721163 is 36112756.

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-65721163 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65721169) 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, 1133095 + ... + 1133152.

It is an arithmetic number, because the mean of its divisors is an integer number (16996860).

Almost surely, 2^65721163 is an apocalyptic number.

65721163 is a deficient number, since it is larger than the sum of its proper divisors (2266277).

65721163 is a wasteful number, since it uses less digits than its factorization.

65721163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2266276.

The product of its digits is 7560, while the sum is 31.

The square root of 65721163 is about 8106.8590095055. The cubic root of 65721163 is about 403.5540839403.

The spelling of 65721163 in words is "sixty-five million, seven hundred twenty-one thousand, one hundred sixty-three".