65666646 has 32 divisors (see below), whose sum is σ = 148406400. Its totient is φ = 21516840.

The previous prime is 65666621. The next prime is 65666647. The reversal of 65666646 is 64666656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65666647) 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, 7120 + ... + 13491.

It is an arithmetic number, because the mean of its divisors is an integer number (4637700).

Almost surely, 2^65666646 is an apocalyptic number.

65666646 is an abundant number, since it is smaller than the sum of its proper divisors (82739754).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65666646 is a wasteful number, since it uses less digits than its factorization.

65666646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20681 (or 20675 counting only the distinct ones).

The product of its digits is 933120, while the sum is 45.

The square root of 65666646 is about 8103.4959122591. The cubic root of 65666646 is about 403.4424677166.

The spelling of 65666646 in words is "sixty-five million, six hundred sixty-six thousand, six hundred forty-six".