65320021 has 12 divisors (see below), whose sum is σ = 71940960. Its totient is φ = 59264400.

The previous prime is 65319997. The next prime is 65320027. The reversal of 65320021 is 12002356.

It is a happy number.

It is not a de Polignac number, because 65320021 - 2⁷ = 65319893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65320027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6696 + ... + 13246.

It is an arithmetic number, because the mean of its divisors is an integer number (5995080).

Almost surely, 2^65320021 is an apocalyptic number.

It is an amenable number.

65320021 is a deficient number, since it is larger than the sum of its proper divisors (6620939).

65320021 is a wasteful number, since it uses less digits than its factorization.

65320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6636 (or 6623 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 65320021 is about 8082.0802396413. The cubic root of 65320021 is about 402.7313506083.

Adding to 65320021 its reverse (12002356), we get a palindrome (77322377).

The spelling of 65320021 in words is "sixty-five million, three hundred twenty thousand, twenty-one".