65936721 has 8 divisors (see below), whose sum is σ = 90751744. Its totient is φ = 42539760.

The previous prime is 65936711. The next prime is 65936737. The reversal of 65936721 is 12763956.

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

It is not a de Polignac number, because 65936721 - 2¹⁹ = 65412433 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 65936721.

It is not an unprimeable number, because it can be changed into a prime (65936711) 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, 354406 + ... + 354591.

It is an arithmetic number, because the mean of its divisors is an integer number (11343968).

Almost surely, 2^65936721 is an apocalyptic number.

It is an amenable number.

65936721 is a deficient number, since it is larger than the sum of its proper divisors (24815023).

65936721 is a wasteful number, since it uses less digits than its factorization.

65936721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709031.

The product of its digits is 68040, while the sum is 39.

The square root of 65936721 is about 8120.1429174615. The cubic root of 65936721 is about 403.9948064065.

The spelling of 65936721 in words is "sixty-five million, nine hundred thirty-six thousand, seven hundred twenty-one".