65721164 has 12 divisors (see below), whose sum is σ = 115137288. Its totient is φ = 32824800.

The previous prime is 65721121. The next prime is 65721169. The reversal of 65721164 is 46112756.

It is a self number, because there is not a number n which added to its sum of digits gives 65721164.

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, 4577 + ... + 12344.

It is an arithmetic number, because the mean of its divisors is an integer number (9594774).

Almost surely, 2^65721164 is an apocalyptic number.

It is an amenable number.

65721164 is a deficient number, since it is larger than the sum of its proper divisors (49416124).

65721164 is a wasteful number, since it uses less digits than its factorization.

65721164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17896 (or 17894 counting only the distinct ones).

The product of its digits is 10080, while the sum is 32.

The square root of 65721164 is about 8106.8590711816. The cubic root of 65721164 is about 403.5540859871.

The spelling of 65721164 in words is "sixty-five million, seven hundred twenty-one thousand, one hundred sixty-four".