641463965 has 4 divisors (see below), whose sum is σ = 769756764. Its totient is φ = 513171168.

The previous prime is 641463961. The next prime is 641464027. The reversal of 641463965 is 569364146.

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 146579449 + 494884516 = 12107^2 + 22246^2 .

It is a cyclic number.

It is not a de Polignac number, because 641463965 - 2² = 641463961 is a prime.

It is a super-2 number, since 2×641463965² = 822952036787042450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641463961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64146392 + ... + 64146401.

It is an arithmetic number, because the mean of its divisors is an integer number (192439191).

Almost surely, 2^641463965 is an apocalyptic number.

It is an amenable number.

641463965 is a deficient number, since it is larger than the sum of its proper divisors (128292799).

641463965 is a wasteful number, since it uses less digits than its factorization.

641463965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128292798.

The product of its digits is 466560, while the sum is 44.

The square root of 641463965 is about 25327.1389027659. The cubic root of 641463965 is about 862.4304625028.

The spelling of 641463965 in words is "six hundred forty-one million, four hundred sixty-three thousand, nine hundred sixty-five".