64642226664661 has 8 divisors (see below), whose sum is σ = 66554873273304. Its totient is φ = 62738293708800.

The previous prime is 64642226664647. The next prime is 64642226664677. The reversal of 64642226664661 is 16646662224646.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 27843626210436 + 36798600454225 = 5276706^2 + 6066185^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 64642226664661 - 2⁵ = 64642226664629 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64642226664661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64642226664161) 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, 2178398140 + ... + 2178427813.

It is an arithmetic number, because the mean of its divisors is an integer number (8319359159163).

Almost surely, 2^{64642226664661} is an apocalyptic number.

It is an amenable number.

64642226664661 is a deficient number, since it is larger than the sum of its proper divisors (1912646608643).

64642226664661 is a wasteful number, since it uses less digits than its factorization.

64642226664661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4356826391.

The product of its digits is 143327232, while the sum is 61.

The spelling of 64642226664661 in words is "sixty-four trillion, six hundred forty-two billion, two hundred twenty-six million, six hundred sixty-four thousand, six hundred sixty-one".