65220247 has 4 divisors (see below), whose sum is σ = 65275056. Its totient is φ = 65165440.

The previous prime is 65220241. The next prime is 65220251. The reversal of 65220247 is 74202256.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65220247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65220241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25579 + ... + 28012.

It is an arithmetic number, because the mean of its divisors is an integer number (16318764).

Almost surely, 2^65220247 is an apocalyptic number.

65220247 is a deficient number, since it is larger than the sum of its proper divisors (54809).

65220247 is a wasteful number, since it uses less digits than its factorization.

65220247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54808.

The product of its (nonzero) digits is 6720, while the sum is 28.

The square root of 65220247 is about 8075.9053362456. The cubic root of 65220247 is about 402.5261935296.

Subtracting 65220247 from its reverse (74202256), we obtain a square (8982009 = 2997²).

The spelling of 65220247 in words is "sixty-five million, two hundred twenty thousand, two hundred forty-seven".