65354221661 has 4 divisors (see below), whose sum is σ = 65359415772. Its totient is φ = 65349027552.

The previous prime is 65354221627. The next prime is 65354221741. The reversal of 65354221661 is 16612245356.

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 18952753561 + 46401468100 = 137669^2 + 215410^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65354221661 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 (65354221561) 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, 2578136 + ... + 2603361.

It is an arithmetic number, because the mean of its divisors is an integer number (16339853943).

Almost surely, 2^65354221661 is an apocalyptic number.

It is an amenable number.

65354221661 is a deficient number, since it is larger than the sum of its proper divisors (5194111).

65354221661 is a wasteful number, since it uses less digits than its factorization.

65354221661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5194110.

The product of its digits is 259200, while the sum is 41.

The spelling of 65354221661 in words is "sixty-five billion, three hundred fifty-four million, two hundred twenty-one thousand, six hundred sixty-one".