811025641 has 2 divisors, whose sum is σ = 811025642. Its totient is φ = 811025640.

The previous prime is 811025639. The next prime is 811025669. The reversal of 811025641 is 146520118.

It is an a-pointer prime, because the next prime (811025669) can be obtained adding 811025641 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 752350041 + 58675600 = 27429^2 + 7660^2 .

It is a cyclic number.

It is not a de Polignac number, because 811025641 - 2¹ = 811025639 is a prime.

Together with 811025639, it forms a pair of twin primes.

It is a Chen prime.

811025641 is a modest number, since divided by 25641 gives 811 as remainder.

It is not a weakly prime, because it can be changed into another prime (811025041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405512820 + 405512821.

It is an arithmetic number, because the mean of its divisors is an integer number (405512821).

Almost surely, 2^811025641 is an apocalyptic number.

It is an amenable number.

811025641 is a deficient number, since it is larger than the sum of its proper divisors (1).

811025641 is an equidigital number, since it uses as much as digits as its factorization.

811025641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 811025641 is about 28478.5119168822. The cubic root of 811025641 is about 932.5630309082.

Adding to 811025641 its reverse (146520118), we get a palindrome (957545759).

The spelling of 811025641 in words is "eight hundred eleven million, twenty-five thousand, six hundred forty-one".