65569921 has 8 divisors (see below), whose sum is σ = 67029120. Its totient is φ = 64126608.

The previous prime is 65569919. The next prime is 65569939. The reversal of 65569921 is 12996556.

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 65569921 - 2¹ = 65569919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65569121) 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, 4575 + ... + 12331.

It is an arithmetic number, because the mean of its divisors is an integer number (8378640).

Almost surely, 2^65569921 is an apocalyptic number.

It is an amenable number.

65569921 is a deficient number, since it is larger than the sum of its proper divisors (1459199).

65569921 is a wasteful number, since it uses less digits than its factorization.

65569921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7943.

The product of its digits is 145800, while the sum is 43.

The square root of 65569921 is about 8097.5256097156. The cubic root of 65569921 is about 403.2442841605.

The spelling of 65569921 in words is "sixty-five million, five hundred sixty-nine thousand, nine hundred twenty-one".