65694221 has 4 divisors (see below), whose sum is σ = 65711100. Its totient is φ = 65677344.

The previous prime is 65694157. The next prime is 65694247. The reversal of 65694221 is 12249656.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 21949225 + 43744996 = 4685^2 + 6614^2 .

It is a cyclic number.

It is not a de Polignac number, because 65694221 - 2⁶ = 65694157 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 (65694281) 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, 695 + ... + 11483.

It is an arithmetic number, because the mean of its divisors is an integer number (16427775).

Almost surely, 2^65694221 is an apocalyptic number.

It is an amenable number.

65694221 is a deficient number, since it is larger than the sum of its proper divisors (16879).

65694221 is a wasteful number, since it uses less digits than its factorization.

65694221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16878.

The product of its digits is 25920, while the sum is 35.

The square root of 65694221 is about 8105.1971598475. The cubic root of 65694221 is about 403.4989315374.

The spelling of 65694221 in words is "sixty-five million, six hundred ninety-four thousand, two hundred twenty-one".