641025641 has 4 divisors (see below), whose sum is σ = 641118852. Its totient is φ = 640932432.

The previous prime is 641025631. The next prime is 641025643. The reversal of 641025641 is 146520146.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 146520146 = 2 ⋅73260073.

It can be written as a sum of positive squares in 2 ways, for example, as 583705600 + 57320041 = 24160^2 + 7571^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-641025641 is a prime.

It is a Duffinian number.

641025641 is a modest number, since divided by 25641 gives 641 as remainder.

It is not an unprimeable number, because it can be changed into a prime (641025643) 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, 35390 + ... + 50343.

It is an arithmetic number, because the mean of its divisors is an integer number (160279713).

Almost surely, 2^641025641 is an apocalyptic number.

It is an amenable number.

641025641 is a deficient number, since it is larger than the sum of its proper divisors (93211).

641025641 is an equidigital number, since it uses as much as digits as its factorization.

641025641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93210.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 641025641 is about 25318.4841765853. The cubic root of 641025641 is about 862.2339795996.

Adding to 641025641 its reverse (146520146), we get a palindrome (787545787).

The spelling of 641025641 in words is "six hundred forty-one million, twenty-five thousand, six hundred forty-one".