65647221 has 16 divisors (see below), whose sum is σ = 92593536. Its totient is φ = 41285376.

The previous prime is 65647193. The next prime is 65647229. The reversal of 65647221 is 12274656.

It is not a de Polignac number, because 65647221 - 2⁷ = 65647093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65647229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1480 + ... + 11553.

It is an arithmetic number, because the mean of its divisors is an integer number (5787096).

Almost surely, 2^65647221 is an apocalyptic number.

It is an amenable number.

65647221 is a deficient number, since it is larger than the sum of its proper divisors (26946315).

65647221 is a wasteful number, since it uses less digits than its factorization.

65647221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13132.

The product of its digits is 20160, while the sum is 33.

The square root of 65647221 is about 8102.2972668250. The cubic root of 65647221 is about 403.4026827152.

The spelling of 65647221 in words is "sixty-five million, six hundred forty-seven thousand, two hundred twenty-one".