65455280721 has 6 divisors (see below), whose sum is σ = 94546516610. Its totient is φ = 43636853808.

The previous prime is 65455280651. The next prime is 65455280743. The reversal of 65455280721 is 12708255456.

65455280721 is a `hidden beast` number, since 6 + 54 + 5 + 528 + 0 + 72 + 1 = 666.

65455280721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 60238830096 + 5216450625 = 245436^2 + 72225^2 .

It is not a de Polignac number, because 65455280721 - 2¹⁰ = 65455279697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65455280771) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3636404476 + ... + 3636404493.

Almost surely, 2^65455280721 is an apocalyptic number.

It is an amenable number.

65455280721 is a deficient number, since it is larger than the sum of its proper divisors (29091235889).

65455280721 is a wasteful number, since it uses less digits than its factorization.

65455280721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7272808975 (or 7272808972 counting only the distinct ones).

The product of its (nonzero) digits is 672000, while the sum is 45.

The spelling of 65455280721 in words is "sixty-five billion, four hundred fifty-five million, two hundred eighty thousand, seven hundred twenty-one".