536821781 has 2 divisors, whose sum is σ = 536821782. Its totient is φ = 536821780.

The previous prime is 536821739. The next prime is 536821783. The reversal of 536821781 is 187128635.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 501312100 + 35509681 = 22390^2 + 5959^2 .

It is a cyclic number.

It is not a de Polignac number, because 536821781 - 2⁶ = 536821717 is a prime.

It is a super-2 number, since 2×536821781² = 576355249112023922, which contains 22 as substring.

Together with 536821783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (536821783) 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 as a sum of consecutive naturals, namely, 268410890 + 268410891.

It is an arithmetic number, because the mean of its divisors is an integer number (268410891).

Almost surely, 2^536821781 is an apocalyptic number.

It is an amenable number.

536821781 is a deficient number, since it is larger than the sum of its proper divisors (1).

536821781 is an equidigital number, since it uses as much as digits as its factorization.

536821781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80640, while the sum is 41.

The square root of 536821781 is about 23169.4147746550. The cubic root of 536821781 is about 812.7245453070.

The spelling of 536821781 in words is "five hundred thirty-six million, eight hundred twenty-one thousand, seven hundred eighty-one".