641688719 has 4 divisors (see below), whose sum is σ = 733358544. Its totient is φ = 550018896.

The previous prime is 641688701. The next prime is 641688721. The reversal of 641688719 is 917886146.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 917886146 = 2 ⋅458943073.

It is not a de Polignac number, because 641688719 - 2¹² = 641684623 is a prime.

It is a super-2 number, since 2×641688719² = 823528824183721922, 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 (641688319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45834902 + ... + 45834915.

It is an arithmetic number, because the mean of its divisors is an integer number (183339636).

Almost surely, 2^641688719 is an apocalyptic number.

641688719 is a deficient number, since it is larger than the sum of its proper divisors (91669825).

641688719 is an equidigital number, since it uses as much as digits as its factorization.

641688719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91669824.

The product of its digits is 580608, while the sum is 50.

The square root of 641688719 is about 25331.5755333141. The cubic root of 641688719 is about 862.5311759087.

The spelling of 641688719 in words is "six hundred forty-one million, six hundred eighty-eight thousand, seven hundred nineteen".