65605661 has 8 divisors (see below), whose sum is σ = 72279648. Its totient is φ = 59050000.

The previous prime is 65605621. The next prime is 65605667. The reversal of 65605661 is 16650656.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65605661 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65605667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28415 + ... + 30636.

It is an arithmetic number, because the mean of its divisors is an integer number (9034956).

Almost surely, 2^65605661 is an apocalyptic number.

It is an amenable number.

65605661 is a deficient number, since it is larger than the sum of its proper divisors (6673987).

65605661 is a wasteful number, since it uses less digits than its factorization.

65605661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59163.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 65605661 is about 8099.7321560654. The cubic root of 65605661 is about 403.3175359035.

It can be divided in two parts, 65605 and 661, that added together give a palindrome (66266).

The spelling of 65605661 in words is "sixty-five million, six hundred five thousand, six hundred sixty-one".