821768071 has 2 divisors, whose sum is σ = 821768072. Its totient is φ = 821768070.

The previous prime is 821768063. The next prime is 821768131. The reversal of 821768071 is 170867128.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 821768071 - 2³ = 821768063 is a prime.

It is a super-2 number, since 2×821768071² = 1350605525030122082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821768471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410884035 + 410884036.

It is an arithmetic number, because the mean of its divisors is an integer number (410884036).

Almost surely, 2^821768071 is an apocalyptic number.

821768071 is a deficient number, since it is larger than the sum of its proper divisors (1).

821768071 is an equidigital number, since it uses as much as digits as its factorization.

821768071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 37632, while the sum is 40.

The square root of 821768071 is about 28666.4973619031. The cubic root of 821768071 is about 936.6624017711.

The spelling of 821768071 in words is "eight hundred twenty-one million, seven hundred sixty-eight thousand, seventy-one".