65642661 has 24 divisors (see below), whose sum is σ = 114738624. Its totient is φ = 35303040.

The previous prime is 65642653. The next prime is 65642671. The reversal of 65642661 is 16624656.

It is a happy number.

65642661 is a `hidden beast` number, since 6 + 5 + 642 + 6 + 6 + 1 = 666.

65642661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 65642661 - 2³ = 65642653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65642641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29575 + ... + 31716.

It is an arithmetic number, because the mean of its divisors is an integer number (4780776).

Almost surely, 2^65642661 is an apocalyptic number.

It is an amenable number.

65642661 is a deficient number, since it is larger than the sum of its proper divisors (49095963).

65642661 is a wasteful number, since it uses less digits than its factorization.

65642661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61321 (or 61318 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 65642661 is about 8102.0158602659. The cubic root of 65642661 is about 403.3933420871.

The spelling of 65642661 in words is "sixty-five million, six hundred forty-two thousand, six hundred sixty-one".