641312616565 has 4 divisors (see below), whose sum is σ = 769575139884. Its totient is φ = 513050093248.

The previous prime is 641312616521. The next prime is 641312616587. The reversal of 641312616565 is 565616213146.

It is a happy number.

641312616565 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 369869532561 + 271443084004 = 608169^2 + 521002^2 .

It is a cyclic number.

It is not a de Polignac number, because 641312616565 - 2¹³ = 641312608373 is a prime.

It is a super-2 number, since 2×641312616565² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64131261652 + ... + 64131261661.

It is an arithmetic number, because the mean of its divisors is an integer number (192393784971).

Almost surely, 2^641312616565 is an apocalyptic number.

It is an amenable number.

641312616565 is a deficient number, since it is larger than the sum of its proper divisors (128262523319).

641312616565 is a wasteful number, since it uses less digits than its factorization.

641312616565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128262523318.

The product of its digits is 777600, while the sum is 46.

The spelling of 641312616565 in words is "six hundred forty-one billion, three hundred twelve million, six hundred sixteen thousand, five hundred sixty-five".