641381477885 has 4 divisors (see below), whose sum is σ = 769657773468. Its totient is φ = 513105182304.

The previous prime is 641381477861. The next prime is 641381477911. The reversal of 641381477885 is 588774183146.

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 413611051876 + 227770426009 = 643126^2 + 477253^2 .

It is a cyclic number.

It is not a de Polignac number, because 641381477885 - 2²⁸ = 641113042429 is a prime.

It is a super-2 number, since 2×641381477885² (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, 64138147784 + ... + 64138147793.

It is an arithmetic number, because the mean of its divisors is an integer number (192414443367).

Almost surely, 2^641381477885 is an apocalyptic number.

It is an amenable number.

641381477885 is a deficient number, since it is larger than the sum of its proper divisors (128276295583).

641381477885 is a wasteful number, since it uses less digits than its factorization.

641381477885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128276295582.

The product of its digits is 36126720, while the sum is 62.

The spelling of 641381477885 in words is "six hundred forty-one billion, three hundred eighty-one million, four hundred seventy-seven thousand, eight hundred eighty-five".