641505677 has 4 divisors (see below), whose sum is σ = 650293500. Its totient is φ = 632717856.

The previous prime is 641505671. The next prime is 641505713. The reversal of 641505677 is 776505146.

641505677 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 178997641 + 462508036 = 13379^2 + 21506^2 .

It is a cyclic number.

It is not a de Polignac number, because 641505677 - 2²⁰ = 640457101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641505671) 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, 4393802 + ... + 4393947.

It is an arithmetic number, because the mean of its divisors is an integer number (162573375).

Almost surely, 2^641505677 is an apocalyptic number.

It is an amenable number.

641505677 is a deficient number, since it is larger than the sum of its proper divisors (8787823).

641505677 is an equidigital number, since it uses as much as digits as its factorization.

641505677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8787822.

The product of its (nonzero) digits is 176400, while the sum is 41.

The square root of 641505677 is about 25327.9623538886. The cubic root of 641505677 is about 862.4491556389.

The spelling of 641505677 in words is "six hundred forty-one million, five hundred five thousand, six hundred seventy-seven".