816571541 has 2 divisors, whose sum is σ = 816571542. Its totient is φ = 816571540.

The previous prime is 816571499. The next prime is 816571543. The reversal of 816571541 is 145175618.

816571541 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 699390916 + 117180625 = 26446^2 + 10825^2 .

It is a cyclic number.

It is not a de Polignac number, because 816571541 - 2²⁶ = 749462677 is a prime.

It is a super-2 number, since 2×816571541² = 1333578163142229362, which contains 22 as substring.

Together with 816571543, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 816571495 and 816571504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (816571543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408285770 + 408285771.

It is an arithmetic number, because the mean of its divisors is an integer number (408285771).

Almost surely, 2^816571541 is an apocalyptic number.

It is an amenable number.

816571541 is a deficient number, since it is larger than the sum of its proper divisors (1).

816571541 is an equidigital number, since it uses as much as digits as its factorization.

816571541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 33600, while the sum is 38.

The square root of 816571541 is about 28575.7159315388. The cubic root of 816571541 is about 934.6838669296.

The spelling of 816571541 in words is "eight hundred sixteen million, five hundred seventy-one thousand, five hundred forty-one".