821411081 has 2 divisors, whose sum is σ = 821411082. Its totient is φ = 821411080.

The previous prime is 821411053. The next prime is 821411099. The reversal of 821411081 is 180114128.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 719097856 + 102313225 = 26816^2 + 10115^2 .

It is a cyclic number.

It is not a de Polignac number, because 821411081 - 2²⁶ = 754302217 is a prime.

It is a super-3 number, since 3×821411081³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 821411081.

It is not a weakly prime, because it can be changed into another prime (821401081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410705540 + 410705541.

It is an arithmetic number, because the mean of its divisors is an integer number (410705541).

Almost surely, 2^821411081 is an apocalyptic number.

It is an amenable number.

821411081 is a deficient number, since it is larger than the sum of its proper divisors (1).

821411081 is an equidigital number, since it uses as much as digits as its factorization.

821411081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 512, while the sum is 26.

The square root of 821411081 is about 28660.2700789787. The cubic root of 821411081 is about 936.5267481098.

The spelling of 821411081 in words is "eight hundred twenty-one million, four hundred eleven thousand, eighty-one".