664226641 has 4 divisors (see below), whose sum is σ = 715321012. Its totient is φ = 613132272.

The previous prime is 664226623. The next prime is 664226657. The reversal of 664226641 is 146622466.

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 244140625 + 420086016 = 15625^2 + 20496^2 .

It is a cyclic number.

It is not a de Polignac number, because 664226641 - 2¹⁹ = 663702353 is a prime.

It is a super-2 number, since 2×664226641² = 882394061228285762, which contains 22 as substring.

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 664226641.

It is not an unprimeable number, because it can be changed into a prime (664226611) 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, 25547166 + ... + 25547191.

It is an arithmetic number, because the mean of its divisors is an integer number (178830253).

Almost surely, 2^664226641 is an apocalyptic number.

It is an amenable number.

664226641 is a deficient number, since it is larger than the sum of its proper divisors (51094371).

664226641 is a wasteful number, since it uses less digits than its factorization.

664226641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51094370.

The product of its digits is 82944, while the sum is 37.

The square root of 664226641 is about 25772.5947665345. The cubic root of 664226641 is about 872.5133824435.

The spelling of 664226641 in words is "six hundred sixty-four million, two hundred twenty-six thousand, six hundred forty-one".